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1. Multistep Photochemical Reactions of Polypyridine-Based Ruthenium Nitrosyl Complexes in Dimethylsulfoxide

Author

Nataliia Marchenko, Pascal G. Lacroix, Valerii Bukhanko, Marine Tassé, Carine Duhayon, Martial Boggio-Pasqua, and Isabelle Malfant

Subjects
nitric oxide, DFT computations, photochemistry, ruthenium complexes, Organic chemistry, QD241-441
Abstract

The photorelease of nitric oxide (NO·) has been investigated in dimethylsulfoxide (DMSO) on two compounds of formula [Ru(R-tpy)(bpy)(NO)](PF6)3, in which bpy stands for 2,2′-bipyridine and R-tpy for the 4′-R-2,2′:6′,2″-terpyridine with R = H and MeOPh. It is observed that both complexes are extremely sensitive to traces of water, leading to an equilibrium between [Ru(NO)] and [Ru(NO2)]. The photoproducts of formula [Ru(R-tpy)(bpy)(DMSO)](PF6)2 are further subjected to a photoreaction leading to a reversible linkage isomerization between the stable Ru-DMSO(S) (sulfur linked) and the metastable Ru-DMSO(O) (oxygen linked) species. A set of 4 [Ru(R-tpy)(bpy)(DMSO)]2+ complexes (R = H, MeOPh, BrPh, NO2Ph) is investigated to characterize the ratio and mechanism of the isomerization which is tentatively related to the difference in absorbance between the Ru-DMSO(S) and Ru-DMSO(O) forms. In addition, the X-ray crystal structures of [Ru(tpy)(bpy)(NO)](PF6)3 and [Ru(MeOPh-tpy)(bpy)(DMSO(S))](PF6)2 are presented.

Published
2020
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2. State of the Art of Boron and Tin Complexes in Second- and Third-Order Nonlinear Optics §

Author

Cristina C. Jiménez, Alejandro Enríquez-Cabrera, Oscar González-Antonio, Javier Ordóñez-Hernández, Pascal G. Lacroix, Pablo Labra-Vázquez, Norberto Farfán, and Rosa Santillan

Subjects
organoboron complex, organotin complex, nonlinear optics, two-photon absorption, Second-Harmonic Generation, Inorganic chemistry, QD146-197
Abstract

Boron and tin complexes have been a versatile and very interesting scaffold for the design of nonlinear optical (NLO) chromophores. In this paper we present a wide range of reports since the 1990s to date, which include second-order (e.g., second harmonic generation) and third-order (e.g., two-photon absorption) NLO properties. After a short introduction on the origin of the NLO response in molecules, the different features associated with the introduction of these inorganic motifs in the organic-based NLO materials are discussed: Their effect on the accepting/donating capabilities of the substituents, on the efficiency of the π-conjugated linkage, and on the topology of the chromophores which can be tuned from the first generation of “push-pull„ chromophores to more sophisticated two- or three-dimensional architectures.

Published
2018
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3. Bimetallic Ruthenium Nitrosyl Complexes with Enhanced Two‐Photon Absorption Properties for Nitric Oxide Delivery

Author

Yael Juarez‐Martinez, Pablo Labra‐Vázquez, Alejandro Enríquez‐Cabrera, Andrés F. Leon‐Rojas, Diego Martínez‐Bourget, Pascal G. Lacroix, Marine Tassé, Sonia Mallet‐Ladeira, Norberto Farfán, Rosa Santillan, Gabriel Ramos‐Ortiz, Jean‐Pierre Malval, Isabelle Malfant, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Centro de Investigaciones en Optica (CIO), Consejo Nacional de Ciencia y Tecnología [Mexico] (CONACYT), Institut de Science des Matériaux de Mulhouse (IS2M), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), IRP-MCCM French-Mexican International Research Program, LIA-LCMMC International Laboratory / CNRS - CONACyT, Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and Gulli, Marie-Hélène

Subjects
Photons, Photochemistry, Organic Chemistry, Ruthenium nitrosyl, General Chemistry, [CHIM.COOR] Chemical Sciences/Coordination chemistry, Nitric Oxide, Ligands, Ruthenium, Catalysis, Ligand design, Density functional calculations, Two-photon absorption, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Density Functional Theory
Abstract

International audience; One monometallic and three bimetallic ruthenium nitrosyl (RuNO) complexes are presented and fully characterized in reference to a parent monometallic complex of formula [FTRu(bpy)(NO)]3+, where FT is a fluorenyl-substituted terpyridine ligand, and bpy the 2,2’-bipyridine. These new complexes are built with the new ligands FFT, TFT, TFFT, and TF-CC-TF (where an alkyne C≡C group is inserted between two fluorenes). The crystal structures of the bis-RuNO2 and bis-RuNO complexes built from the TFT ligand are presented. The evolution of the spectroscopic features (intensities and energies) along the series, at one-photon absorption (OPA) correlates well with the TD-DFT computations. A spectacular effect is observed at two-photon absorption (TPA) with a large enhancement of the molecular cross-section (σTPA), in the bimetallic species. In the best case, σTPA is equal to 1523±98 GM at 700 nm, in the therapeutic window of transparency of biological tissues. All compounds are capable of releasing NO⋅ under irradiation, which leads to promising applications in TPA-based drug delivery.

Published
2022

4. Two-Photon-Triggered NO Release via a Ruthenium–Nitrosyl Complex with a Star-Shaped Architecture

Author

Pascal G. Lacroix, Rosa Santillan, Gabriel Ramos-Ortiz, Rana Mhanna, Jean-Pierre Malval, Isabelle Malfant, Andrés Felipe León-Rojas, Norberto Farfán, Margarita Romero Ávila, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Institut de Science des Matériaux de Mulhouse (IS2M), Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Centro de Investigaciones en Optica (CIO), Consejo Nacional de Ciencia y Tecnología [Mexico] (CONACYT), PAPIIT (IN222819), PAIP, CONACYT, Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Gulli, Marie-Hélène, Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, chemistry.chemical_element, 010402 general chemistry, 01 natural sciences, Absorption, Molecular engineering, chemistry.chemical_compound, Absorption spectroscopy, Two-photon excitation microscopy, [CHIM.COOR]Chemical Sciences/Coordination chemistry, General Materials Science, Z-scan technique, Physical and Theoretical Chemistry, Absorption (electromagnetic radiation), No release, 010405 organic chemistry, [CHIM.COOR] Chemical Sciences/Coordination chemistry, 0104 chemical sciences, Ruthenium, chemistry, Coupling (computer programming), Chemical physics, Irradiation, Group theory, Terpyridine, Electron paramagnetic resonance spectroscopy
Abstract

International audience; We report herein a molecular engineering strategy based on the design of a multipolar ruthenium–nitrosyl (Ru–NO) complex with a three-branched architecture. The three Ru–NO units are introduced at the periphery of a highly π-delocalized truxene core bearing three terpyridine ligands. The two-photon absorption capabilities of the complex were investigated by the Z-scan technique. The strong electronic coupling among the individual arms gives rise to a very strong two-photon absorption response (δ800 nm ∼ 1600 GM), which corresponds to a 16-fold enhancement of the capability of a single-arm reference, thereby promoting an efficient light-driven NO release process in aqueous media.

Published
2020

5. Terre en 4D : apport des séries temporelles de modèles numériques d'élévation par photogrammétrie spatiale pour l'étude de la surface terrestre

Author

Pascal G. Lacroix, Laurent Polidori, Simon Gascoin, Etienne Berthier, César Deschamps-Berger, Centre d'études spatiales de la biosphère (CESBIO), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), and Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)

Subjects
QA71-90, HE9713-9715, Applied optics. Photonics, Electrical and Electronic Engineering, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Instruments and machines, Cellular telephone services industry. Wireless telephone industry, TA1501-1820, Computer Science Applications
Abstract

International audience; This article presents a review of the applications in geosciences of digital elevation model (DEM) time series from satellite stereoscopic imagery for the observation of geometric changes at the Earth's surface. This method dates back to the beginning of the 2000's as a consequence of the multiplication of imaging satellites. We present the evolution of the data availability from the birth of the method for military purpose to its propagation in the civilian sphere. The various methods used for analysing series of digital elevation models are presented, as well as their applications in glaciology, hydrology, volcanology, seismology and geomorphology. Given the constant improvement of the image quality and resolution, the range of applications should continue to grow.; Cet article présente une revue des applications en géosciences des séries temporelles de modèles numériques d'élévation (MNE) calculés par photogrammétrie spatiale pour l'observation des changements géométriques à la surface terrestre. Les premières utilisations de MNE dans ce contexte émergent au début des années 2000, facilitées par la multiplication des satellites imageurs haute ou moyenne résolution. La disponibilité des images satellite stéréoscopiques est retracée depuis ses débuts militaires jusqu'à sa propagation dans le civil. Les différentes méthodes de traitements de MNE multi-temporels sont présentées ainsi que leur utilisation dans les travaux scientifiques en glaciologie, hydrologie, volcanologie, sismologie, et en géomorphologie. Grâce à l'amélioration constante de la qualité et résolution des images, le spectre des phénomènes observés devrait continuer de s'étendre..

Published
2020

6. Rain and small earthquakes maintain a slow-moving landslide in a persistent critical state

Author

Edu Taipe, Pascal G. Lacroix, Eric Larose, Jorge Jara, Noélie Bontemps, Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Université Grenoble Alpes (UGA), Laboratoire de géologie de l'ENS (LGENS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Instituto Geológico Minero y Metalúrgico (INGEMMET), École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris)

Subjects
010504 meteorology & atmospheric sciences, Precipitaciones, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Science, Movimientos en masa, General Physics and Astronomy, 010502 geochemistry & geophysics, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Article, Large earthquakes, Natural hazard, Statistical analysis, lcsh:Science, Deslizamientos, Seismology, 0105 earth and related environmental sciences, Multidisciplinary, Natural hazards, Landslide, General Chemistry, Sismicidad, Geophysics, 13. Climate action, Erosion, lcsh:Q, Geology, Evotranspiración
Abstract

In tectonically active mountain belts, landslides contribute significantly to erosion. Statistical analysis of regional inventories of earthquake-triggered-landslides after large earthquakes (Mw > 5.5) reveal a complex interaction between seismic shaking, landslide material, and rainfall. However, the contributions of each component have never been quantified due to a lack of in-situ data for active landslides. We exploited a 3-year geodetic and seismic dataset for a slow-moving landslide in Peru affected by local earthquakes and seasonal rainfalls. Here we show that in combination, they cause greater landslide motion than either force alone. We also show the rigidity of the landslide’s bulk clearly decreasing during Ml ≥ 5 earthquakes. The recovery is affected by rainfall and small earthquakes (Ml, In this study, the authors show the interaction between seismic activity and rainfalls on landslide movement and how their timing controls landslide stability and motion.

Published
2020

7. A massive rock and ice avalanche caused the 2021 disaster at Chamoli, Indian Himalaya

Author

Jakob F. Steiner, Kshitiz Upadhyay, Martin Mergili, David N. Petley, Kaushal Raj Gnyawali, Shashank Bhushan, Mylène Jacquemart, Adam Emmer, Simon Gascoin, M. Dokukin, Simon J. Cook, Abhishek Kumar, Dan H. Shugar, Etienne Berthier, Cameron S. Watson, Matthew J. Westoby, Sandy Harrison, Wolfgang Schwanghart, Summer Rupper, Sara K. McBride, Ulfat Majeed, Irfan Rashid, Simon Allen, A. P. Dimri, F. Ugalde, Christian Huggel, Pascal G. Lacroix, Arnab Muhuri, M. Van Wyk de Vries, Holger Frey, Jeannette Noetzli, Silvan Leinss, John J. Clague, César Deschamps-Berger, Mark McDonnell, Frank Paul, Mats Eriksson, M. Jha, Daniel Farinotti, J. L. Kavanaugh, Andreas Kääb, Jonathan L. Carrivick, Michele Koppes, Jeffrey S. Kargel, Umesh K. Haritashya, Ashim Sattar, Stuart Dunning, Mohd Farooq Azam, Joel Fiddes, Rakesh Bhambri, Kalachand Sain, David Shean, Suraj Mal, Centre d'études spatiales de la biosphère (CESBIO), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), and Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Grenoble Alpes (UGA)-Université Gustave Eiffel-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])

Subjects
geography, Multidisciplinary, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, business.industry, Glacier, F800, 010502 geochemistry & geophysics, 01 natural sciences, Debris flow, 13. Climate action, Satellite imagery, Physical geography, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, business, Geology, Hydropower, 0105 earth and related environmental sciences
Abstract

International audience; On 7 February 2021, a catastrophic mass flow descended the Ronti Gad, Rishiganga, and Dhauliganga valleys in Chamoli, Uttarakhand, India, causing widespread devastation and severely damaging two hydropower projects. More than 200 people were killed or are missing. Our analysis of satellite imagery, seismic records, numerical model results, and eyewitness videos reveals that~27 × 10 6 cubic meters of rock and glacier ice collapsed from the steep north face of Ronti Peak. The rock and ice avalanche rapidly transformed into an extraordinarily large and mobile debris flow that transported boulders greater than 20 meters in diameter and scoured the valley walls up to 220 meters above the valley floor. The intersection of the hazard cascade with downvalley infrastructure resulted in a disaster, which highlights key questions about adequate monitoring and sustainable development in the Himalaya as well as other remote, high-mountain environments.

Published
2021

8. Rockfall and vulnerability of mountaineers on the west face of the Aiguille du Goûter (classic route up Mont Blanc, France), an interdisciplinary study

Author

Guilhem Marsy, Marco Marcer, Ludovic Ravanel, Jacques Mourey, P.A Duvillard, Emmanuel Malet, and Pascal G. Lacroix

Subjects
geography, Rockfall, geography.geographical_feature_category, Mountaineering, Snowmelt, Vulnerability, Climate change, Physical geography, Couloir, Training (civil), Tourism
Abstract

In high alpine environments, climate change leads to an increase in rockfall destabilizations. They represent a threat for sports and tourism activities in high mountain and especially for mountaineering. This danger of rockfall is particularly important on the classic route up Mont Blanc (4,809 m a.s.l., Mont Blanc massif, France), on the west face of the Aiguille du Goûter (3,863 m a.s.l.), and is responsible for at least 29 % of the accidents that occur in this sector. Despite the intensity of the geomorphological processes at work and the vulnerability of climbers, few scientific studies have been carried out on the occurrence of rockfalls and their triggering factors in the Goûter area. Based on a multi-method monitoring system (5 seismic sensors, an automatic digital camera, 3 subsurface temperature sensors, a pyroelectric sensor, a high-resolution topographical survey, 2 weather stations and a rain gauge) the objective of our study is therefore to quantitatively document the occurrence of rockfalls and their triggering factors in the Grand Couloir du Goûter in order to better assess the vulnerability of mountaineers in this sector. Our results show that in the high-Alpine and permafrost-affected Aiguille du Goûter west face, rockfalls are mostly frequent during the snowmelt period which favors the action of thermo-mechanical processes linked to the infiltration of liquid water into the cracks of the rock. During periods when the couloir is completely clear of snow, rockfalls are 2.5 times less frequent, and the thermo-mechanical processes involved in the rockfall triggering are limited by the absence of moisture in the ground. These results also show that climbers' awareness of the risk of rockfalls remains limited. What’s more, they do not adapt – or only slightly – their behavior to this risk, despite a particularly high accident rate. Important work on prevention and dissemination of the knowledge here acquired (newsletters, training for professionals and amateurs, awareness campaigns) among mountaineers is therefore still really necessary.

Published
2021

9. Far-field coseismic forcing of giant rockslides in the 2017 Sarpol-Zahab Earthquake (Iran)

Author

Aya Cheaib, Najmeh Ajorlou, James Hollingsworth, Pascal G. Lacroix, Swann Zerathe, Marie-Pierre Doin, Chadi Abdallah, and Denis Jongmans

Subjects
Rockslide, Forcing (mathematics), Geology, Seismology
Abstract

On November 12th 2017, the largest earthquake (Mw 7.3) ever recorded in the Zagros mountains occurred near the town of Sarpol-Zahab, Iran. While this region encompasses clusters of giant ancient ro...

Published
2021

10. Multi-method investigation of mass transfer mechanisms in a retrogressive clayey landslide (Harmaliere, French Alps)

Author

Guillaume Chambon, Sylvain Fiolleau, Pascal G. Lacroix, Marc Wathelet, Denis Jongmans, Michel Demierre, Agnès Helmstetter, Grégory Bièvre, Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Grenoble Alpes (UGA)-Université Gustave Eiffel-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Erosion torrentielle neige et avalanches (UR ETGR (ETNA)), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), InfraSurvey Sarl, French VOR federative structure, French national C2ROP project, project SIMOTER 1 - European Union under the ERDF -POIA program, French government under the FNADT -CIMA program, ANR-15-IDEX-0002,UGA,IDEX UGA(2015), and ANR-10-LABX-0056,OSUG@2020,Innovative strategies for observing and modelling natural systems(2010)

Subjects
021110 strategic, defence & security studies, Earthflow, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], 0211 other engineering and technologies, Landslide, 02 engineering and technology, Slip (materials science), Headscarp, Geotechnical Engineering and Engineering Geology, Retrogression, Aerial photography, Passive seismic, Mass transfer, Natural hazard, Clayey landslide, Multi method, Geology, Seismology, 021101 geological & geomatics engineering
Abstract

International audience; The mass transfer mechanisms in landslides are complex to monitor because of their suddenness and spatial coverage. The active clayey Harmalière landslide, located 30 km south of Grenoble in the French Alps, exhibits two types of behavior: in its upper part, decameter-sized clay blocks slide along a listric slip surface, while a flow-like mechanism is observed in a clayey remolded material a few hundred meters below the headscarp. The landslide underwent a major retrogression affecting 45 ha in March 1981 and has experienced multiple reactivations since then. The last major event took place on the 26th of June 2016, and a large investigation survey was conducted to better understand the reactivation mechanism. A multi-method investigation was carried out at different temporal and spatial scales, including aerial photograph and light detection and ranging processing, correlation of optical satellite images, global navigation satellite system monitoring, continuous seismic monitoring, and passive seismic survey. The morphological evolution of the landslide was traced over the last 70 years, showing a headscarp retrogression of 700 m during multiple reactivations and a total mass transfer of more than 6 × 106 m3. The detailed study of the 2016 event allowed to track and understand the mechanism of a mass transfer of 1 × 106 m3 in 5 weeks, from a sliding mechanism at the headscarp to an earthflow at the toe.

Published
2021

11. Physicochemical and computational insight of 19 F NMR and emission properties of meso -( o -aryl)-BODIPYs

Author

Armando Ariza, Mónica Farfán-Paredes, Oscar González-Antonio, Rosa Santillan, Norberto Farfán, Pascal G. Lacroix, Diana E. Tahuilan-Anguiano, Jorge Peon, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Instituto de Quı́mica, Universidad Nacional Autónoma de México, Universidad Nacional Autónoma de México (UNAM), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Farmácia da Universidade do Porto, Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), CONACYT A1-S-7642, PAIP and PAPIIP IN222819, and French-Mexican International Laboratory (LIA-LCMMC-CONACYT FONCYT 069/2018)

Subjects
010405 organic chemistry, Aryl, chemistry.chemical_element, General Chemistry, Fluorine-19 NMR, 010402 general chemistry, 01 natural sciences, Catalysis, Spectral line, 0104 chemical sciences, Rotational energy, Electronegativity, chemistry.chemical_compound, chemistry, Computational chemistry, Materials Chemistry, Fluorine, Molecule, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Quantum
Abstract

International audience; A series of electronic and physicochemical parameters were explored to determine their effect on experimental spectroscopic and photophysical data. Through a systematic obtention of a series of meso-(o-aryl)-BODIPYs, 19F NMR spectra were analyzed and their fluorescence quantum yields in several solvents were measured. Experimental values of 19F chemical shift difference ΔδF correlate well with σ-Hammett constants, which is indicative of the inductive nature of the functional groups on the fluorine atoms. A computational DFT exploration of rotational energy barriers, electrostatic potential maps, group electronegativity, charge partitions and hardness/softness provided insight into how those traits can be directly related to the measured features. Expanded understanding of such characteristics provides design arguments and a structure–property relationship, which in a more advantageous way, would help to understand the properties of the synthesized molecules and of future attempts that are structurally related.

Published
2020

12. Chemical and photochemical behavior of ruthenium nitrosyl complexes with terpyridine ligands in aqueous media

Author

Pascal G. Lacroix, Norberto Farfán, Sonia Mallet-Ladeira, Isabelle Malfant, Marine Tassé, Mathilde Bocé, Pablo Labra-Vázquez, Universidad Nacional Autónoma de México (UNAM), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), CNRS (France), CONACyT, PAPIIT (Programa de Apoyo a Proyectos de Investigación e Innovación Tecnológica), Mexico, University Paul Sabatier (COMUE), and Région Midi-Pyrénées - RuNOthérapie grant

Subjects
Aqueous medium, 010405 organic chemistry, Ligand, chemistry.chemical_element, Crystal structure, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, 0104 chemical sciences, Ruthenium, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Density functional theory, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Computational analysis, Terpyridine
Abstract

International audience; The synthesis and behavior in water of a set of various cis(Cl,Cl)-[R-tpyRuCl2(NO)](PF6) and trans(Cl,Cl)-[R-tpyRuCl2(NO)](PF6) (R = fluorenyl, phenyl, thiophenyl; tpy = 2,2′:6′,2′′-terpyridine) complexes are presented. In any case, one chlorido ligand is substituted by a hydroxo ligand and the final species arises as a single trans(NO,OH) isomer, whatever the nature of the starting cis/trans(Cl,Cl) complexes. Six X-ray crystal structures are presented for cis(Cl,Cl)-[thiophenyl-tpyRuCl2(NO)](PF6) (cis-3a), trans(Cl,Cl)-[thiophenyl-tpyRuCl2(NO)](PF6) (trans-3a), trans(NO,OH)-[phenyl-tpyRu(Cl)(OH)(NO)](PF6) (4a), trans(NO,OH)-[thiophenyl-tpyRu(Cl)(OH)(NO)](PF6) (4b), trans(NO,OEt)-[phenyl-tpyRu(Cl)(OEt)(NO)](PF6) (5a), and trans(NO,OH)-[phenyl-tpyRu(Cl)(OEt)(NO)](PF6) (5b) compounds. The different cis/trans(Cl,Cl) complexes exhibit an intense low-lying transition in the λ = 330–390 nm range, which appears to be slightly blue-shifted after Cl → OH substitution. In water, both cis/trans(Cl,Cl) isomers are converted to a single trans(NO,OH) isomer in which one chlorido- is replaced by one hydroxo-ligand, which avoids tedious separation workout. The water stable trans(NO,OH)-species all release NO with quantum yields of 0.010 to 0.075 under irradiation at 365 nm. The properties are discussed with computational analysis performed within the framework of Density Functional Theory.

Published
2020

13. Tuning the Cell Uptake and Subcellular Distribution in BODIPY–Carboranyl Dyads: An Experimental and Theoretical Study

Author

Norberto Farfán, Arturo Jiménez-Sánchez, Ricardo Flores-Cruz, Pablo Labra-Vázquez, Justo Cabrera-González, Pascal G. Lacroix, Cristian Guzmán‐Cedillo, Rosario Núñez, Aylin Galindo‐Hernández, Rosa Santillan, Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Instituto de Quı́mica, Universidad Nacional Autónoma de México, Institut de Ciència de Materials de Barcelona (ICMAB), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), PAPIIT (IN222819), CONACyT (A1-S-7642), Spanish Ministerio de Economia y Competitividad, MICINN (PID2019-106832RB-100), Generalitat de Catalunya (2017/SGR/1720), Universidad Nacional Autónoma de México (UNAM), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional Autónoma de México, Consejo Nacional de Ciencia y Tecnología (México), Ministerio de Economía y Competitividad (España), and Generalitat de Catalunya

Subjects
Boron Compounds, Fluorophore, Sonogashira coupling, [CHIM.THER]Chemical Sciences/Medicinal Chemistry, Fluorophores, 010402 general chemistry, 01 natural sciences, Catalysis, Imaging, chemistry.chemical_compound, Boron neutron capture therapy, BODIPY, Humans, [CHIM.COOR]Chemical Sciences/Coordination chemistry, 010405 organic chemistry, Organic Chemistry, General Chemistry, Models, Theoretical, Subcellular localization, Fluorescence, 0104 chemical sciences, 3. Good health, Partition coefficient, chemistry, Theranostic, Lipophilicity, BNCT, Biophysics, Carborane, HeLa Cells
Abstract

A set of BODIPY‐carboranyl dyads synthesized by a Sonogashira cross‐coupling reaction, where different C‐substituted ortho‐ and meta‐carboranyl fragments have been linked to a BODIPY fluorophore is described. Chemical, photophysical and physicochemical analyses are presented, including NMR and SXRD experiments, optical absorption/emission studies and log P measurements. These studies, supported by DFT computations (M06‐2X/6‐31G**) provide an explanation to the largely divergent cell income that these fluorescent carboranyl‐based fluorophores display, for which a structural or physicochemical explanation remains elusive. By studying the cell uptake efficiency and subcellular localization for our set of dyads on living HeLa cells, we tracked the origins of these differences to significant variations in their static dipole moments and partition coefficients, which tune their ability to interact with lipophilic microenvironments in cells. Remarkably, m‐carboranyl‐BODIPY derivatives with a higher lipophilicity are much better internalised by cells than their homologous with o‐carborane, suggesting that m‐isomers are potentially better theranostic agents for in vitro bioimaging and boron carriers for BNCT., The work has been performed within the framework of the French-Mexican International Laboratory (LIA-LCMMC). Authors acknowledge support from PAPIIT (IN222819) and CONACyT. The work was supported by Spanish Ministerio de Economía y Competitividad, MINECO (CTQ2016-75150-R) and Generalitat de Catalunya (2017/SGR/1720). Doctoral scholarships were granted by CONACyT to P.L.-V (337958) and R. F.-C. (576635). We thank María E. Ochoa (CINVESTAV-IPN), Marco A. Leyva (CINVESTAV-IPN) and Flor R. Vega (FQ-UNAM) for NMR/HRMS experiments, SXRD experiments and technical support, correspondingly.

Published
2020

14. Two-photon absorption properties of four new pentacoordinated diorganotin complexes derived from Schiff bases with fluorene

Author

Rosa Santillan, Pascal G. Lacroix, Violeta Álvarez-Venicio, Alejandro Enriquez‐Cabrera, Margarita Romero-Ávila, Gabriel Ramos-Ortiz, Norberto Farfán, Alberto Vega-Peñaloza, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Centro de Investigaciones en Optica (CIO), Consejo Nacional de Ciencia y Tecnología [Mexico] (CONACYT), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV)

Subjects
NonLinear optics, 010405 organic chemistry, Organic Chemistry, Chromophore, Fluorene, 010402 general chemistry, DFT, 01 natural sciences, Biochemistry, Two-photon absorption, Fluorescence, Spectral line, 0104 chemical sciences, Inorganic Chemistry, Crystallography, chemistry.chemical_compound, chemistry, Atomic electron transition, Diorganotin complexes, Excited state, Materials Chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Spectroscopy
Abstract

International audience; In this paper we report the synthesis and characterization of four novel pentacoordinated diorganotin complexes, obtained through a methodology that involves a multicomponent reaction of 4-([9H-fluorene-2-yl]ethynyl)-2-hydroxybenzaldehyde, 2-amino-5-nitrophenol and diphenyl or dibutyl-tin oxides. Diorganotin complexes 8–11 were obtained in high yields (70–80%) and were fully characterized by solution NMR (1H, 13C and 119Sn), high resolution mass spectrometry (ESI-TOF) and ATR-FTIR. The optical properties were investigated by UV/Vis spectroscopy and Two-Photon Excitation Fluorescence (TPEF). The One-Photon Absorption (OPA) spectra shows two bands located around 400 and 500 nm, additionally, in the Two-Photon Absorption (TPA) spectra there is one main band located around 750 nm characterized by maximum values of TPA cross section (σTPA) in the range 450–500 GM with a secondary band located at 1000 nm with maximum σTPA values of 70 GM; the maximum brightness was observed for 2,2-Dibutyl-6-aza-1,3-dioxa-11-([9,9-dihexyl-9H-fluorene-2-yl]ethynyl)-16-nitro-2-stanna-[d,h]dibenzocyclononene with a value of 150 GM. A theoretical approach within the framework of DFT was applied to study the electronic transitions, showing that the 500 nm band is mainly associated to a HOMO→LUMO transition, and the band at 400 nm to a HOMO-1→LUMO transition. As main highlights the quantum efficiency of fluorescence of these excited states is as large as 0.43 due to the presence of the tin atom which favors molecular rigidity, these compounds possess TPA responses which are significantly enhanced with respect to related organotin chromophores previously reported.

Published
2018

15. Author Correction: Effect of trans(NO, OH)-[RuFT(Cl)(OH)NO](PF6) ruthenium nitrosyl complex on methicillin-resistant Staphylococcus epidermidis

Author

Marie-Pierre Rols, Charlotte Da Silva, Isabelle Malfant, Mathilde Bocé, Pascal G. Lacroix, Flavien Pillet, Marine Tassé, Patricia Vicendo, and Sonia Mallet-Ladeira

Subjects
Multidisciplinary, Chemistry, lcsh:R, lcsh:Medicine, Methicillin-resistant Staphylococcus epidermidis, chemistry.chemical_element, lcsh:Q, lcsh:Science, Medicinal chemistry, Ruthenium
Abstract

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Published
2019

16. Satellite Pre-Failure Detection and In Situ Monitoring of the Landslide of the Tunnel du Chambon, French Alps

Author

Pascal G. Lacroix, Ombeline Brenguier, and Mathilde Desrues

Subjects
Satellite observation, 010504 meteorology & atmospheric sciences, Pleiades, medium-scale landslides, lcsh:QE1-996.5, pre-failure motions, detection, Geodetic datum, Landslide, 010502 geochemistry & geophysics, Geodesy, 01 natural sciences, Pléiades satellites, lcsh:Geology, satellites, Satellite data, General Earth and Planetary Sciences, Satellite, Stage (hydrology), in-situ geodetic measurements, Geology, 0105 earth and related environmental sciences
Abstract

Recent studies using satellite data have shown a growing interest in detecting and anticipating landslide failures. However, their value for an actual landslide prediction has shown variable results. Therefore, the use of satellite images for that purpose still requires additional attention. Here, we study the landslide of the Tunnel du Chambon in the French Alps that ruptured in July 2015, generating major impacts on economic activity and infrastructures. To evaluate the contribution of very high-resolution optical satellite images to characterize and potentially anticipate the landslide failure, we conduct here a retro analysis of its evolution. Two time periods are analyzed: September 2012 to September 2014, and May to July 2015. We combine Pl&eacute, iades optical images analysis and geodetic measurements from in situ topographic monitoring. Satellite images were correlated to detect pre-failure motions, showing 1.4-m of displacement between September 2012 and September 2014. In situ geodetic measures were used to analyze motions during the main activity of the landslide in June and July 2015. Topographic measurements highlight different areas of deformations and two periods of strong activity, related to the last stage of the tertiary creep and to anthropic massive purges of unstable masses. The law of acceleration toward the rupture observed in June and July 2015 over the topographic targets also fits well the satellite observation between 2012 and 2014, showing that the landslide probably already entered into tertiary creep 2.5 years before its failure.

Published
2019
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17. Further studies on the photoreactivities of ruthenium–nitrosyl complexes with terpyridyl ligands

Author

Isabelle Malfant, Pascal G. Lacroix, Alix Sournia-Saquet, Silvia Amabilino, Marine Tassé, Isabelle Sasaki, Sonia Mallet-Ladeira, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK., Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), University of Warwick [Coventry], and Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV]Life Sciences [q-bio], Substituent, Quantum yield, chemistry.chemical_element, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Medicinal chemistry, Catalysis, 3. Good health, 0104 chemical sciences, Ruthenium, chemistry.chemical_compound, chemistry, Nitrosamine, Group (periodic table), Materials Chemistry, Moiety, [CHIM]Chemical Sciences, 0210 nano-technology, Derivative (chemistry), Cis–trans isomerism
Abstract

International audience; This study focuses on the two cis/trans-(Cl,Cl)-[Ru(R-Phtpy)Cl2(NO)]+ isomers, where the R group is a NEt2 substituent on the 4′-position of the phenylterpyridine (Phtpy) moiety. The photophysical characteristic properties of the two isomers and those of one nitrosamine derivative are described. The NO release properties are evaluated and show that the cis isomer is the most efficient with a good quantum yield of NO release. The X-ray structures of three ruthenium–nitrosyl complexes and of a photoproduct are presented.

Published
2019

18. Self‐Entrainment Motion of a Slow‐Moving Landslide Inferred From Landsat‐8 Time Series

Author

James Hollingsworth, Gael Araujo, Edu Taipe, Pascal G. Lacroix, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Observatorio Vulcanológico del INGEMMET (Dirección de Geología Ambiental y Riesgo Geológico) [Arequipa], and Observatorio Vulcanológico del INGEMMET (Dirección de Geología Ambiental y Riesgo Geológico)

Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, 010504 meteorology & atmospheric sciences, Series (mathematics), [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], 0211 other engineering and technologies, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Landslide, 02 engineering and technology, Geodesy, 01 natural sciences, Motion (physics), Displacement (vector), Geophysics, [SDU]Sciences of the Universe [physics], Entrainment (chronobiology), Geology, ComputingMilieux_MISCELLANEOUS, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract

International audience

Published
2019

19. Effect of trans(NO, OH)-[RuFT(Cl)(OH)NO](PF6) ruthenium nitrosyl complex on methicillin-resistant Staphylococcus epidermidis

Author

Sonia Mallet-Ladeira, Marine Tassé, Flavien Pillet, Pascal G. Lacroix, Charlotte Da Silva, Marie-Pierre Rols, Isabelle Malfant, Mathilde Bocé, Patricia Vicendo, Laboratoire de chimie de coordination (LCC), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut de pharmacologie et de biologie structurale (IPBS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Interactions moléculaires et réactivité chimique et photochimique (IMRCP), Université de Toulouse (UT)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Fédération de Recherche Fluides, Energie, Réacteurs, Matériaux et Transferts (FERMAT), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), IDeAS - Interfaces Dynamiques et Assemblages Stimulables (IDeAS), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT), French National Center for Scientific Research (CNRS), University Paul Sabatier (COMUE), Région Midi-Pyrénées - RuNOthérapie, Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)

Subjects
0301 basic medicine, medicine.drug_class, Antibiotics, lcsh:Medicine, Microbial Sensitivity Tests, Article, Ruthenium, Microbiology, 03 medical and health sciences, Methicillin, 0302 clinical medicine, Antibiotic resistance, Staphylococcus epidermidis, medicine, Humans, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Mode of action, lcsh:Science, Author Correction, Multidisciplinary, biology, Chemistry, lcsh:R, Biofilm, Biofilm matrix, Methicillin-resistant Staphylococcus epidermidis, Staphylococcal Infections, biology.organism_classification, 3. Good health, Anti-Bacterial Agents, 030104 developmental biology, Biofilms, lcsh:Q, Methicillin Resistance, 030217 neurology & neurosurgery, Bacteria
Abstract

Antibiotic resistance is becoming a global scourge with 700,000 deaths each year and could cause up to 10 million deaths by 2050. As an example, Staphylococcus epidermidis has emerged as a causative agent of infections often associated with implanted medical devices. S. epidermidis can form biofilms, which contribute to its pathogenicity when present in intravascular devices. These staphylococci, embedded in the biofilm matrix, are resistant to methicillin, which had long been the recommended therapy and which has nowadays been replaced by less toxic and more stable therapeutic agents. Moreover, current reports indicate that 75 to 90% of Staphylococcus epidermidis isolates from nosocomial infections are methicillin-resistant strains. The challenge of successfully combating antibiotics resistance in biofilms requires the use of compounds with a controlled mode of action that can act in combination with antibiotics. Ruthenium nitrosyl complexes are potential systems for NO release triggered by light. The influence of trans(NO, OH)-[RuFT(Cl)(OH)NO](PF6) on Staphylococcus epidermidis resistant to methicillin is described. The results show a 50% decrease in cell viability in bacteria treated with low concentrations of NO. When combined with methicillin, this low dose of NO dramatically decreases bacterial resistance and makes bacteria 100-fold more sensitive to methicillin.

Published
2019

20. Nitric oxide (NO) photo-release in a series of ruthenium–nitrosyl complexes: new experimental insights in the search for a comprehensive mechanism

Author

Max Roose, Pascal G. Lacroix, Marine Tassé, Isabelle Malfant, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Ministère de l’Enseignement Supérieur et de la Recherche (MESR)

Subjects
Ligand, chemistry.chemical_element, Electron donor, 02 engineering and technology, General Chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Catalysis, Spectral line, 0104 chemical sciences, Ruthenium, Nitric oxide, chemistry.chemical_compound, Crystallography, chemistry, Intramolecular force, Pyridine, Materials Chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Irradiation, 0210 nano-technology
Abstract

International audience; A series of four ruthenium(ii) complexes built from the [Ru(terpy)(bipy)(NO)](3+) core (terpy is 2,2:6,2-terpyridine and bipy is 2,2-bipyridine) are investigated. They differ by the presence of zero, one, two, or three 4-(4-methoxyphenyl) (MP) electron donor substituents introduced at different positions on the pyridine fragments to increase the intramolecular charge transfer capabilities towards the strongly withdrawing nitrosyl (NO) ligand. The UV-visible spectra reflect the presence and position of the MP substituents on the complexes. In the case of species containing the 4-(MP)-terpy ligand, a low-lying transition is identified as arising from 4-(MP)-terpy to Ru(NO) intramolecular charge transfer, which is further confirmed by TD-DFT analysis. Irradiation performed at = 436 nm on this isolated transition for different complexes leads to quantum yields of NO photo-release equal to 0.002 and 0.011, in a ratio of 6 (instead of 1), which allows concluding non-ambiguously that a single electron transition cannot account for the NO release mechanism.

Published
2019

21. Detection of Pre-eruptive Seismic Velocity Variations at an Andesitic Volcano Using Ambient Noise Correlation on 3-Component Stations: Ubinas Volcano, Peru, 2014

Author

Eric Larose, Roger Machacca-Puma, Pascal G. Lacroix, Philippe Lesage, Rosa M. Anccasi-Figueroa, Instituto Geológico Minero y Metalúrgico (INGEMMET), Institut des Sciences de la Terre (ISTerre), and Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
Volcano monitoring, 010504 meteorology & atmospheric sciences, Ambient noise level, volcano seismology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Coda wave interferometry, 010502 geochemistry & geophysics, 01 natural sciences, Coda, eruption precursor, Impact crater, Geochemistry and Petrology, Waveform, coda wave interferometry, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, volcano monitoring, Volcano seismology, Andesite, Horizontal plane, Eruption precursor, Geophysics, Amplitude, Volcano, 13. Climate action, Seismic velocity variation, Seismology, Geology, Ubinas volcano
Abstract

International audience; Volcano monitoring and eruption forecasting are based on the observation and joined interpretation of several precursory phenomena. It is thus important to detect new types of precursor and to study their relationship with forthcoming eruptions. In the last years, variations of seismic velocity have been observed in some volcanoes, mainly basaltic, before eruptions. In this paper, we look for velocity variations and waveform decorrelations before the 2014 eruptive sequence of the andesitic Ubinas volcano in Peru. We compute velocity changes by using seismic ambient noise cross-correlation (between pairs of stations) and cross-components correlation (between vertical and horizontal components of single stations), as well as coda wave interferometry of seismic multiplets. With these different approaches, we show that the major explosions that occurred from 13 to 19 April were preceded by a clear velocity decrease and waveform decorrelation. The amplitude of velocity change is generally larger on single-station cross-components correlation than on two-stations cross-correlation in all the frequency ranges tested (between 0.1 and 8 Hz). We highlight an apparent anisotropy of velocity change in single-station cross-components correlation, with larger amplitudes when correlating vertical and tangential components than using vertical and radial components with respect to the crater. The Mw = 8.1 Iquique earthquake on 1 April 2014 produced also a marked co-seismic velocity drop detected in a high frequency range (3-5 Hz) in both single-station cross-components correlation and cross-correlations. We locate in the horizontal plane and in depth the velocity perturbation and the structural change related with decorrelation. During the main phase of eruptive activity, the velocity decrease at low frequency (0.1-1 Hz) appears to affect the whole edifice mainly at depth of about 1 to 3 km below the surface. The structural perturbation is more concentrated on the south flank of the volcano, a zone that corresponds to an ancient collapse. We suggest that the observed velocity variations are due to the dilatation of the edifice and to microfracturation induced by magma pres-surization. The structural change may be locally enhanced by a possible zone of material weakness in the southern sector. The co-seismic velocity perturbation is located mostly in the southeast flank, at depth smaller than 0.5 to 1 km, and may be related to the presence of the hydrothermal system of the volcano.

Published
2019

22. State of the Art of Boron and Tin Complexes in Second- and Third-Order Nonlinear Optics §

Author

Pascal G. Lacroix, Alejandro Enriquez‐Cabrera, Cristina C. Jiménez, Norberto Farfán, Javier Ordóñez-Hernández, Oscar González-Antonio, Rosa Santillan, Pablo Labra-Vázquez, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV)

Subjects
Materials science, Nonlinear optics, Second-Harmonic Generation, chemistry.chemical_element, Organotin complex, 010402 general chemistry, 01 natural sciences, Two-photon absorption, Inorganic Chemistry, lcsh:Inorganic chemistry, Molecule, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Boron, Topology (chemistry), Organoboron complex, 010405 organic chemistry, business.industry, Second-harmonic generation, Chromophore, lcsh:QD146-197, 0104 chemical sciences, chemistry, Optoelectronics, Tin, business
Abstract

International audience; Boron and tin complexes have been a versatile and very interesting scaffold for the design of nonlinear optical (NLO) chromophores. In this paper we present a wide range of reports since the 1990s to date, which include second-order (e.g., second harmonic generation) and third-order (e.g., two-photon absorption) NLO properties. After a short introduction on the origin of the NLO response in molecules, the different features associated with the introduction of these inorganic motifs in the organic-based NLO materials are discussed: Their effect on the accepting/donating capabilities of the substituents, on the efficiency of the _-conjugated linkage, and on the topology of the chromophores which can be tuned from the first generation of “push-pull” chromophores to more sophisticated two- or three-dimensional architectures.

Published
2018

23. Light induced nonlinear optical switch in boronated chromophores: A theoretical search towards high contrast switches in the azobenzene series

Author

Isabelle Malfant, Rosa Santillan, Cristina C. Jiménez, Norberto Farfán, Pascal G. Lacroix, Margarita Romero-Ávila, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, ESIQIE, UPALM, Instituto Politécnico Nacional, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Molecular switch, Ligand, Organic Chemistry, 02 engineering and technology, Crystal structure, Chromophore, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, 01 natural sciences, Biochemistry, 0104 chemical sciences, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Azobenzene, Materials Chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Density functional theory, Physical and Theoretical Chemistry, 0210 nano-technology, Isomerization, Boron trifluoride
Abstract

International audience; The possibility to obtain molecular nonlinear optical switches with high onloff contrast is discussed in boronated azobenzene derivatives from a computational investigation conducted at the Density Functional Theory (DFT) level. An optimized situation is found in the case of 2-(1-phenylazo-2-naphthol)1,3,2-benzodioxaborole in which the computed NLO response could decrease 8.5 times after E to Z isomerization. Herein is reported the synthesis and characterization of two new phenylazo derivatives prepared from the reaction of the corresponding ligand and boron trifluoride diethyl etherate, to test the synthetic feasibility of these boronated species. The crystal structure of 1-phenylazo-2-naphthalate difluoroborate is presented.

Published
2015

24. Sparsity Optimization Method for Slow-Moving Landslides Detection in Satellite Image Time-Series

Author

Marie-Pierre Doin, Pascal G. Lacroix, Mai Quyen Pham, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA)

Subjects
0211 other engineering and technologies, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Landslide, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], 02 engineering and technology, Synthetic data, Physics::Geophysics, symbols.namesake, [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, Gaussian noise, Norm (mathematics), Outlier, symbols, General Earth and Planetary Sciences, Satellite Image Time Series, [MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC], Electrical and Electronic Engineering, Time series, Image resolution, Algorithm, 021101 geological & geomatics engineering, Mathematics
Abstract

International audience; This paper presents a new method based on recent optimization technique to detect slow-moving landslides (

Published
2018

25. Comparison of carbazole and fluorene donating effects on the two-photon absorption and nitric oxide photo-release capabilities in a ruthenium-nitrosyl complex

Author

Isabelle Malfant, Norberto Farfán, Pascal G. Lacroix, Alejandro Enriquez‐Cabrera, Rodrigo M. Barba-Barba, Isabelle Sasaki, Gabriel Ramos-Ortiz, Sonia Mallet-Ladeira, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Centro de Investigaciones en Optica (CIO), Consejo Nacional de Ciencia y Tecnología [Mexico] (CONACYT), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and Universidad Nacional Autónoma de México (UNAM)

Subjects
Electronic structure, Tertiary amine, Photochemistry, [SDV]Life Sciences [q-bio], chemistry.chemical_element, Quantum yield, Crystal structure, Fluorene, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Ruthenium, Inorganic Chemistry, chemistry.chemical_compound, Charge transfer, [CHIM]Chemical Sciences, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Ruthenium, Nitrogen oxides, Drug delivery, Density functional calculations, Photochemistry, Electronic structure, Charge transfer, 010405 organic chemistry, Carbazole, 0104 chemical sciences, Density functional calculations, chemistry, Drug delivery, Terpyridine, Derivative (chemistry), Nitrogen oxides
Abstract

International audience; A ruthenium–nitrosyl derivative of formula [RuII(CzT)(bipy)(NO)](PF6)3 [CzT = 4′-(N-ethylcarbazol-3-yl)-2,2′:6′,2′′-terpyridine, bipy = 2,2′-bipyridine] has been synthesized and fully characterized, and compared with the previously reported [RuII(FT)(bipy)(NO)](PF6)3 complex [FT = 4′-(9,9-dihexyl-9H-fluoren-2-yl)-2,2′:6′,2′′-terpyridine]. Additionally, the X-ray crystal structure of [RuII(CzT)(bipy)(NO2)](PF6), the precursor of [RuII(CzT)(bipy)(NO)](PF6)3, is reported. The presence of a tertiary amine in the carbazole unit leads to redshifted charge-transfer transitions towards the electron-withdrawing Ru–NO fragment and hence enhanced two-photon absorption (TPA) properties. In contrast, the quantum yield of the NO· photorelease process is lower for the carbazole-containing complex. The issue of optimization of the TPA versus NO·-release capabilities is addressed.

Published
2018

26. Use of Sentinel-2 images for the detection of precursory motions before landslide failures

Author

Denis Jongmans, Grégory Bièvre, Erwan Pathier, Pascal G. Lacroix, and Ulrich Kniess

Subjects
010504 meteorology & atmospheric sciences, Cloud cover, 0211 other engineering and technologies, Soil Science, Precursors, Geology, Landslide, 02 engineering and technology, Geodesy, 01 natural sciences, Displacement (vector), Medium resolution, Acceleration, Lidar, Satellite, Satellite imagery, Computers in Earth Sciences, Sentinel-2, Scale (map), Landslides, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, Optical satellite
Abstract

The Sentinel-2 optical satellites provide a global coverage of land surfaces with a 5-day revisit time at the Equator. We investigate the ability of these freely available optical images to detect precursory motions before rapid landslides. A 9-month time-series of displacement is derived from Sentinel-2 data over a major landslide in the French Alps, which exhibited a sudden reactivation in June 2016. This analysis reveals a 7-month period of low activity (

Published
2018

27. Integration of geotechnical and geophysical techniques for the characterization of a small earth-filled canal dyke and the localization of water leakage

Author

Guy Monnot, David Goutaland, Yannick Fargier, Pascal G. Lacroix, Grégory Bièvre, Laurent Oxarango, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut des Géosciences de l’Environnement (IGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Recherche pour le Développement (IRD)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Direction Centre-Est (Cerema Direction Centre-Est), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Direction Normandie-Centre (Cerema Direction Normandie-Centre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Laboratoire d'étude des transferts en hydrologie et environnement (LTHE), Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), and Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)

Subjects
010504 meteorology & atmospheric sciences, EROSION, Water flow, Geophysical imaging, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], DIGUE, Geometry, Water head, 010502 geochemistry & geophysics, 01 natural sciences, INTERNAL EROSION, Internal erosion, LEAKAGE, FUITE, Geotechnical engineering, Electrical resistivity tomography, TOMOGRAPHIE, 0105 earth and related environmental sciences, geography, WATER HEAD, Hydrogeology, geography.geographical_feature_category, VIBRATION, GEOMETRY, Bedrock, Geophysics, GEOPHYSIQUE, Love wave, Earth-filled canal dyke, Levee, Leakage, EARTH-FILLED CANAL DYKE, Geology, Seismology
Abstract

This paper investigates the combined use of extensive geotechnical, hydrogeological and geophysical techniques to assess a small earth dyke with a permanent hydraulic head, namely a canal embankment. The experimental site was chosen because of known issues regarding internal erosion and piping phenomena. Two leakages were visually located following the emptying of the canal prior to remediation works. The results showed a good agreement between the geophysical imaging techniques (Electrical Resistivity Tomography, P- and SH-waves Tomography) and the geotechnical data to detect the depth to the bedrock and its lateral variations. It appeared that surface waves might not be fully adapted for dyke investigation because of the particular geometry of the studied dyke, non-respectful of the 1D assumption, and which induced depth and velocity discrepancies retrieved from Rayleigh and Love waves inversion. The use of these classical prospecting techniques however did not allow to directly locate the two leakages within the studied earth dyke. The analysis of ambient vibration time series with a modified beam-forming algorithm allowed to localize the most energetic water flow prior to remediation works. It was not possible to detect the leakage after remediation works, suggesting that they efficiently contributed to significantly reduce the water flow. The second leakage was not detected probably because of a non-turbulent water flow, generating few energetic vibrations.

Published
2017

28. Coseismic and postseismic motion of a landslide: Observations, modeling, and analogy with tectonic faults

Author

Pascal G. Lacroix, Bertrand Guillier, Hugo Perfettini, and Edu Taipe

Subjects
Triggering, Earthquake, Terremotos, Landslide classification, Movimientos en masa, Landslide, Active fault, Slip (materials science), Rate and state friction, Tectónica, Tectonics, Geophysics, Coeficiente de fricción, General Earth and Planetary Sciences, Deslizamientos, Modelos tectónicos, Geology, Seismology
Abstract

We document the first time series of a landslide reactivation by an earthquake using continuous GPS measurements over the Maca landslide (Peru). Our survey shows a coseismic response of the landslide of about 2 cm, followed by a relaxation period of 5 weeks during which postseismic slip is 3 times greater than the coseismic displacement itself. Our results confirm the coseismic activation of landslides and provide the first observation of a postseismic displacement. These observations are consistent with a mechanical model where slip on the landslide basal interface is governed by rate and state friction, analogous to the mechanics of creeping tectonic faults, opening new perspectives to study the mechanics of landslides and active faults.

Published
2014

29. Supervised Method of Landslide Inventory Using Panchromatic SPOT5 Images and Application to the Earthquake-Triggered Landslides of Pisco (Peru, 2007, Mw8.0)

Author

Laurence Audin, Etienne Berthier, Pascal G. Lacroix, Bilberto Zavala, Institut des Sciences de la Terre (ISTerre), Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), INGEMMET, Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Instituto Geológico Minero y Metalúrgico (INGEMMET), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Soil cover, [SDE.MCG]Environmental Sciences/Global Changes, SATELLITE SPOT, IMAGE SATELLITE, detection, optical imagery, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], 010502 geochemistry & geophysics, 01 natural sciences, GLISSEMENT DE TERRAIN, topography, Peru, Satellite imagery, TELEDETECTION, lcsh:Science, Deslizamientos, Forearc, 0105 earth and related environmental sciences, Remote sensing, Inventario, landslides, Pixel, Orientation (computer vision), Terremotos, Imágenes de satélite, Orthophoto, VALIDATION DE RESULTAT, ETUDE REGIONALE, Landslide, TOPOGRAPHIE, Panchromatic film, SPOT5, triggering, power-law, 13. Climate action, inventories, earthquake, General Earth and Planetary Sciences, SISMOLOGIE, lcsh:Q, Sensores remotos, Geology, METHODOLOGIE
Abstract

International audience; Earthquake is one of the dominant triggering factors of landslides. Given the wide areas covered by mega earthquake-triggered landslides, their inventory requires development of automatic or semi-automatic methods applied to satellite imagery. A detection method is here proposed for this purpose, to fit with simple datasets; SPOT5 panchromatic images of 5 m resolution coupled with a freely and globally available DEM. The method takes advantage of multi-temporal images to detect changes based on radiometric variations after precise coregistration/orthorectification. Removal of false alarms is then undertaken using shape, orientation and radiometric properties of connected pixels defining objects. 80% of the landslides and 93% of the landslide area are detected indicating small omission errors but 50% of false alarms remain. They are removed using expert based analysis of the inventory. The method is applied to realize the first comprehensive inventory of landslides triggered by the Pisco earthquake (Peru, 15/08/2007, Mw 8.0) over an area of 27,000 km2. 866 landslides larger than 100 m2 are detected covering a total area of 1.29 km2. The area/number distribution follows a power-law with an exponent of 1.63, showing a very particular regime of triggering in this arid environment compared to other areas in the world. This specific triggering can be explained by the little soil cover in the coastal and forearc regions of Peru. Analysis of this database finally shows a major control of the topography (both orientation and inclination) on the repartition of the Pisco-triggered landslides.

Published
2013

30. MULTI-PROPERTY MATERIALS - MAGNETISM AND NLO PROPERTIES

Author

René Cléement, Dermot O'Hare, John S. O. Evans, and Pascal G. Lacroix

Subjects
Property (philosophy), Materials science, Mechanics of Materials, Magnetism, Mechanical Engineering, Mineralogy, Nonlinear optics, General Materials Science, Nanotechnology
Published
2016

31. Isoindole and isomeric heterocyclic donating substituents in ruthenium(II)nitrosyl complexes with large first hyperpolarizabilities and potential two-photon absorption capabilities: a computational approach

Author

Zoia Voitenko, Pascal G. Lacroix, Valerii Bukhanko, Isabelle Malfant, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, Taras Shevchenko National University of Kyiv, Taras Shevchenko National University of Kyiv, Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
010405 organic chemistry, Carbazole, Substituent, chemistry.chemical_element, Fluorene, 010402 general chemistry, Photochemistry, 01 natural sciences, Two-photon absorption, 0104 chemical sciences, Ruthenium, chemistry.chemical_compound, chemistry, Computational chemistry, Density functional theory, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Terpyridine, Isoindole
Abstract

International audience; A set of 22 ruthenium nitrosyl complexes of general formula [RuII(L)Cl2(NO)]+ is investigated computationally by the density functional theory. L is a terpyridine ligand substituted by different R isomers of formula C12H8N, either indole, isoindole, or carbazole, proposed as alternative donors to the electron-rich fluorene substituent. The computed resulting nonlinear optical (NLO) properties are found to strongly depend on the isomer. While the ruthenium complexes exhibit modest efficiencies at the second-order (two-photon absorption) level, some of the R isomers lead to complexes of enhanced capabilities in first order (b) nonlinear optics. The synthetic feasibility of these ligands is discussed.

Published
2016

32. Landslides triggered by the Gorkha earthquake in the Langtang valley, volumes and initiation processes

Author

Pascal G. Lacroix

Subjects
010504 meteorology & atmospheric sciences, Mass movement, Seismic triggering, Landslide classification, DEM, Geology, Landslide, Vegetation, 010502 geochemistry & geophysics, Snow, Volumes, Optical satellite photogrammetry, 01 natural sciences, Debris, Debris avalanche, Nepal, SPOT, Space and Planetary Science, Serac, Digital surface, Geomorphology, Seismology, Landslides, 0105 earth and related environmental sciences
Abstract

The Gorkha earthquake (Nepal, 2015, M w 7.9) triggered many landslides. The most catastrophic mass movement was a debris avalanche that buried several villages in the Langtang valley. In this study, questions are raised about its volume and initiation. I investigate the possibility of high-resolution digital surface models computed from tri-stereo SPOT6/7 images to resolve this issue. This high-resolution dataset enables me to derive an inventory of 160 landslides triggered by this earthquake. I analyze the source of errors and estimate the uncertainties in the landslide volumes. The vegetation prevents to correctly estimate the volumes of landslides that occured in vegetated areas. However, I evaluate the volume and thickness of 73 landslides developing in vegetated-free areas, showing a power law between their surface areas and volumes with exponent of 1.20. Accumulations and depletion volumes are also well constrained for larger landslides, and I find that the main debris avalanches accumulated 6.95 × 106 m3 of deposits in the valley with thicknesses reaching 60 m, and 9.66 × 106 m3 in the glaciated part above 5000 m asl. The large amount of sediments is explained by an initiation of the debris avalanche due to serac falls and snow avalanches from five separate places between 6800 and 7200 m asl over 3 km length.

Published
2016

33. Synthesis, crystal structure and non-linear optical properties of boronates derivatives of salicylideniminophenols

Author

Norberto Farfán, Margarita Romero, Gabriel Ramos-Ortiz, Rosa Santillan, B. Muñoz, José M. Méndez, Pascal G. Lacroix, Keitaro Nakatani, José-Luis Maldonado, and Mario Rodríguez

Subjects
Aryl, Organic Chemistry, Condensation, chemistry.chemical_element, One-Step, Crystal structure, Carbon-13 NMR, Mass spectrometry, Biochemistry, Inorganic Chemistry, Crystallography, chemistry.chemical_compound, chemistry, Materials Chemistry, Physical and Theoretical Chemistry, Boron, Spectroscopy
Abstract

The condensation in one step of a series of salicylaldehydes and 2-amino-5-nitrophenol with 1-naphthylboronic acid, 2-naphthylboronic acid, and o-tolylboronic acid to give the corresponding boronates 1a–3a, 1b–3b and 1c–3d, is reported. The X-ray crystal structures of 1a, 2b and 3b allowed determining the a- and b-angle between the stilbene skeleton and the aryl or naphthylboronic fragments; these values are indicative of different conformations for the aryl moieties around the (B–C) boron–carbon bond which could potentially modulate the electronic properties on the boron stilbene compounds. All compounds were characterized by 1 H, 11 B and 13 C NMR spectroscopy, UV, IR and mass spectrometry. Second- and third-order non-linear optical characterizations were also performed by EFISH and THG Maker Fringe techniques, respectively. Compounds 3a–3d containing an –N(Et)2 donor group gave the best NLO response in second- and third-order. 2008 Elsevier B.V. All rights reserved.

Published
2008

34. Rifting processes and ice-flow modulation observed on Mertz Glacier, East Antarctica

Author

C. Mayet, Benoit Legresy, Neal Young, Richard Coleman, Lydie Lescarmontier, Pascal G. Lacroix, and Laurent Testut

Subjects
geography, Rift, Glacier terminus, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Ice stream, Tidewater glacier cycle, crevasses, Glacier, 010502 geochemistry & geophysics, Geodesy, 01 natural sciences, glacier mechanics, Iceberg, Antarctic glaciology, Glacier mass balance, 13. Climate action, Ice tongue, glacier flow, calving, Geomorphology, Geology, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract

We investigated the evolution of two major rifts cutting across Mertz Glacier Tongue, East Antarctica, using a combination of satellite images and 60 day sets of GPS data from two stations deployed either side of the western rift in 2007. The eastern rift began to open in the early 1990s, and the western rift initiated in 2002 in conjunction with the collision of a large iceberg with the tongue. Velocity time series derived from the 2007 GPS data exhibited strong variations at tidal periods modulated by sea-surface height and sea-surface slope and reproduced here with a conceptually simple model. We found that opening of the western rift in 2002 leads to a dramatic change in behavior of the tongue as the large range in velocity (700–2400 m a−1) observed in 2000 was largely reduced (1075–1225 m a−1) in 2007. Opening of the western rift decoupled the glacier from the transverse loading on the tongue driven by east–west tidal circulation. This loading previously induced time-varying lateral drag, which caused the large velocity range. Our results suggest changes in the mechanical behavior of an ice tongue impact the dynamics of the outlet glacier system and should be considered in longer-term mass-balance evaluations.

Published
2015

35. Synthesis, characterization and nonlinear optical properties in a series of new chiral organotin(IV) Schiff base complexes

Author

Rosa Santillan, Norberto Farfán, Mario Rodríguez, José María Rivera, Jean François Lamère, Pascal G. Lacroix, Keitaro Nakatani, David Guzmán, Departamen to de Quimica, Centro de Investigacio´n y de Estudios Avanzados del IPN, Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Departamento de Quimica Organica, and Facultad de Quimica, Universidad Nacional Autonoma de Mexico

Subjects
Oxide, Crystal structure, 010402 general chemistry, DFT, 01 natural sciences, Biochemistry, Multinuclear NMR, Inorganic Chemistry, chemistry.chemical_compound, Computational chemistry, Electric field, Materials Chemistry, Physical and Theoretical Chemistry, Diorganotin, Schiff base, Series (mathematics), 010405 organic chemistry, Organic Chemistry, Condensation, Second-harmonic generation, NLO properties, 0104 chemical sciences, chemistry, Salicylaldehyde, Physical chemistry, X-ray structure, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph]
Abstract

International audience; Four new chiral organotin derivatives are reported with their crystal structure. They were synthesized by reaction of diphenyltin oxide and four different ligands obtained from the Schiff base condensation of 4-(diethylamino)salicylaldehyde and (1R,2S)-(+)-norephedrine, (R)-()-phenylglycinol, (R)-()-1-amino-2-propanol and (1S,2R)-2-amino-1,2-diphenylethanol. Their nonlinear optical properties were investigated experimentally in solid state and with the electric field induced second harmonic (EFISH) technique. In particular, the compound obtained with (R)-()-phenylglycinol exhibits an efficiency 11 times that of urea in second harmonic generation at 1.907 lm. The properties are discussed in relation with computational studies conducted within the framework of the DFT theory. 2005 Elsevier B.V. All rights reserved.

Published
2006

36. Synthesis and quadratic molecular hyperpolarizabilities of two new chiral boronates: Computational and experimental study

Author

Norberto Farfán, Rosa Santillan, Christine Lepetit, Horacio Reyes, José María Rivera, Pascal G. Lacroix, and Keitaro Nakatani

Subjects
Ligand, Dimer, Organic Chemistry, Analytical chemistry, Hyperpolarizability, Mass spectrometry, Biochemistry, Inorganic Chemistry, Boric acid, chemistry.chemical_compound, Monomer, chemistry, Materials Chemistry, Physical chemistry, Physical and Theoretical Chemistry, Boronic acid, Derivative (chemistry)
Abstract

A monomeric boronate and an oxobridged chiral dimer were obtained by reaction of the ligand derived from 4-diethylaminosalicylaldehyde with (R)-(� )-phenylglycinol, and phenyl boronic acid or boric acid. The compounds were fully characterized by spectroscopic techniques ( 1 H, 13 C, 11 B NMR, elemental analyses, IR and masses spectrometry); and their molecular hyperpolarizabilities were investigated by the electric field induced second harmonic (EFISH) technique and semi-empirical calculations. The experimental quadratic hyperpolarizability which is equal to 9.8 · 10 � 30 cm 5 esu � 1 at 1.064 lm for the monomeric derivative rises

Published
2005

37. Syntheses, crystal structures, and quadratic nonlinear optical properties in four 'push–pull' diorganotin derivatives

Author

Rosa Santillan, Horacio Reyes, Christine Lepetit, Concepción García, Norberto Farfán, Pascal G. Lacroix, and Keitaro Nakatani

Subjects
Organic Chemistry, Intermolecular force, Oxide, chemistry.chemical_element, Crystal structure, Biochemistry, Inorganic Chemistry, Trigonal bipyramidal molecular geometry, Crystallography, chemistry.chemical_compound, chemistry, Computational chemistry, Atom, Octahedral molecular geometry, Materials Chemistry, Physical and Theoretical Chemistry, Tin, Boron
Abstract

Four “push–pull” diorganotin compounds obtained by reaction of methoxysalicylaldehyde or 4-diethylaminosalicylaldehyde, 2-amino-5-nitrophenol and dibutyltin or diphenyltin oxide are reported. The molecular structures for the diphenyl derivatives, in the solid state, show a tin in a distorted trigonal bipyramid geometry with the oxygen atoms in axial positions and the organic moieties and iminic nitrogen in equatorial ones. For the dibutyl derivative, a dimeric structure was favored due to intermolecular interactions between the tin and oxygen atoms, in this case, the tin atom shows a distorted octahedral geometry. A computational study of the diethyl derivatives constructed from the available dibutyl structure, at DFT level, revealed that the main differences between the solid and gas phases are the geometry around the tin atom and the π-conjugated organic backbone which is nearly planar in the solid state and distorted in the gas phase. The electric field induced second-harmonic (EFISH) of the nonlinear optical (NLO) response for the dibutyl derivatives revealed that the change from boron to tin increases 1.5 times the hyperpolarizabilities (β).

Published
2004

38. Synthesis, X-ray diffraction analysis and nonlinear optical properties of hexacoordinated organotin compounds derived from Schiff bases

Author

Norberto Farfán, Violeta Álvarez-Venicio, Keitaro Nakatani, Blanca M. Muñoz-Flores, Rosa Santillan, Mario Rodríguez, Omar G. Morales-Saavedra, Pascal G. Lacroix, Víctor M. Jiménez-Pérez, Christine Lepetit, Universidad Autonoma de Nuevo Leon [Mexique] (UANL), Centro de Investigacion y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Centro de Investigaciones en Optica, Laboratorio de Óptica No Lineal, Centro de Ciencias Aplicadas y Desarrollo Tecnológico [México] (CCADET-UNAM), Universidad Nacional Autónoma de México (UNAM), Laboratoire Culture et Communication (LCC), Avignon Université (AU), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), and École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010405 organic chemistry, Stereochemistry, Chemistry, Ligand, Organic Chemistry, X-ray, chemistry.chemical_element, 010402 general chemistry, Mass spectrometry, 01 natural sciences, Biochemistry, 0104 chemical sciences, Inorganic Chemistry, Crystallography, Elemental analysis, Atom, Octahedral molecular geometry, X-ray crystallography, Materials Chemistry, [CHIM.COOR]Chemical Sciences/Coordination chemistry, Physical and Theoretical Chemistry, Tin
Abstract

International audience; The reaction of N,N-bis(2-hydroxy-4-R-benzylidene)-1,2-phenylendiimine (1 R = OH, 2 R = OMe) with R′2SnO (R′ = Me, n-Bu, Ph) provided six new organotin derivatives: dimethyl-di-n-butyl- and diphenyl[N,N′-bis(3-hydroxysalicylaldehyde)-1,2-phenylenediiminato]tin(IV) (1a), (1b), (1c) as well as dimethyl-di-n-butyl- and diphenyl[N,N′-bis(3-methoxysalicylaldehyde)-1,2-phenylenediiminato]tin(IV), (2a), (2b), (2c), respectively. All compounds were characterized by 1H, 13C and 119Sn-NMR, elemental analysis, UV, IR, and mass spectrometry. Compounds 2a, 2b and 2c were characterized by single-crystal X-ray structure analysis. In the solid state, 2a, 2b, and 2c showed the Schiff bases backbone in a bent arrangement containing a tin atom with distorted octahedral geometry, where the ligand occupies the four equatorial positions and the methyl, n-butyl, or phenyl groups occupy the trans axial positions. The second-order nonlinear optical response of representative organotin compounds 2a–c was estimated by electric field induced second harmonic (EFISH) measurements where interesting βμ values in the promising range of 10–60 × 10−30 esu were evaluated.

Published
2014

39. New chiral ferrocenyl-pyridinium salts for non-linear optics

Author

Eric Manoury, Karine Roque, Gilbert G. A. Balavoine, Fabienne Barangé, Jean-Claude Daran, and Pascal G. Lacroix

Subjects
chemistry.chemical_classification, Organic Chemistry, Iodide, Second-harmonic generation, Nonlinear optics, Crystal structure, Biochemistry, Inorganic Chemistry, Crystal, chemistry.chemical_compound, Crystallography, chemistry, Ferrocene, Materials Chemistry, Pyridinium, Physical and Theoretical Chemistry, Chirality (chemistry)
Abstract

Three enantiomerically pure chiral analogues of 4-[( E )-2-ferrocenyl-ethenyl]pyridinium iodide have been synthesized. Their bulk efficiencies in second harmonic generation (SHG) have been measured (from 0 to 0.25 times that of urea). Furthermore, the crystal structures for two of them and for the parent 4-[( E )-2-ferrocenyl-ethenyl]pyridinium iodide have been determined by X-ray diffraction studies. Crystal packing could explain the very different SHG bulk efficiencies in this family of materials.

Published
2001

40. Synthesis, Crystal Structures, and Second-Order Nonlinear Optical Properties of New Chiral Ferrocenyl Materials

Author

Jacques A. Delaire, and Pascal G. Lacroix, Gilbert G. A. Balavoine, Santo Di Bella, Eric Manoury, and Isabelle Maltey-Fanton, Gabriel Iftime, Keitaro Nakatani, and Jean-Claude Daran

Subjects
Organic Chemistry, Crystal structure, Chromophore, Centrosymmetry, Inorganic Chemistry, Crystal, chemistry.chemical_compound, Crystallography, Ferrocene, chemistry, Cyclopentadienyl complex, Molecule, Physical and Theoretical Chemistry, Chirality (chemistry)
Abstract

A series of chiral enantiomerically pure analogues of (E)-(2-(4-nitrophenyl)ethenyl)ferrocene (2), substituted by R (3, R = Me; 4, R = CH2OH; 5, R = SiMe3), in the 2-position on the cyclopentadienyl ring, were synthesized. Measurements by electric-field-induced second-harmonic generation (EFISH) and calculations by INDOS/CI-SOS show that the different chromophores have closely related molecular NLO responses. However, the crystal packings for the different compounds, observed by X-ray diffraction on a monocrystal, are completely different. In any case, the chirality of the constituting molecules avoids the centrosymmetry of the crystals and therefore preserves the NLO efficiency in the solid state. In the case of 3, the crystal packing is close to the centrosymmetry and so the bulk NLO efficiency is low (6 times that of urea, λ = 1.907 μm) but not nil, as is the case for 2. For 4, the crystal packing is much better for NLO (efficiency 20 times that of urea, λ = 1.907 μm) and is almost optimized for 5 (eff...

Published
1998

41. Synthesis and Second-Order Nonlinear Optical Properties of New Copper(II), Nickel(II), and Zinc(II) Schiff-Base Complexes. Toward a Role of Inorganic Chromophores for Second Harmonic Generation

Author

S. Di Bella, Pascal G. Lacroix, and I. Ledoux

Subjects
General Chemical Engineering, Inorganic chemistry, chemistry.chemical_element, Second-harmonic generation, Hyperpolarizability, General Chemistry, Zinc, Copper, Nickel, chemistry.chemical_compound, chemistry, Salicylaldehyde, Diaminomaleonitrile, Materials Chemistry, Physical chemistry, ZINDO
Abstract

A new Schiff-base ligand based on the condensation of diaminomaleonitrile and 4-(diethylamino)salicylaldehyde is reported with its copper, nickel, and zinc complexes. Their second-order nonlinear optical properties are investigated by electric field induced second harmonic (EFISH) and ZINDO quantum-chemical calculations to probe the role of the metal center in the nonlinearity. All the complexes exhibit a second-order nonlinear response that is larger than that of the ligand with an hyperpolarizability (β) value of 400 (±100) 10-30 cm5 esu-1 for the zinc derivative at 1.34 μm. Theoretical calculations indicate that the two-level model is inadequate to describe the nonlinearity in such systems.

Published
1996

42. Materials Chemistry and Structural Chemistry of Tin Compounds

Author

Geraldo M. de Lima, Thierry Toupance, Esen Arkis, Nikos Chaniotakis, Paul A. Cusack, Pascal G. Lacroix, Norberto Farfn, Bernard Jousseaume, Hemant K. Sharma, Keith H. Pannell, Ionel Haiduc, Edward R. T. Tiekink, and Julio Zukerman-Schpector

Subjects
Chemistry, Organic chemistry
Published
2008

43. Syntheses, Crystal Structures, and NLO Properties of New Chiral Inorganic Chromophores for Second-Harmonic Generation

Author

Keitaro Nakatani, Pascal G. Lacroix, Jean Claude Daran, Géraldine Lenoble, and Santo Di Bella

Subjects
Chemistry, Stereochemistry, Ligand, Chiral ligand, Space group, chemistry.chemical_element, Manganese, Crystal structure, Inorganic Chemistry, chemistry.chemical_compound, Crystallography, Salicylaldehyde, Orthorhombic crystal system, Physical and Theoretical Chemistry, Monoclinic crystal system
Abstract

A new chiral ligand (H(2)L) based on the condensation of diaminocyclohexane and 4-(diethylamino)salicylaldehyde is reported along with its nickel(II) and manganese(III) complexes. These compounds all crystallize in noncentrosymmetric space groups. Crystal data are as follows. For the ligand (C(28)H(40)N(4)O(2)): monoclinic, I2, a = 15.487(2) Å, b = 8.1988(6) Å, c = 20.958(3) Å, beta = 95.92(1) degrees, Z = 4. For the Ni(II)L complex: monoclinic, P2(1), a = 8.613(2) Å, b = 21.714(4) Å, c = 15.870(4) Å, beta = 91.02(2) degrees, Z = 4. For the Mn(III)LCl complex: orthorhombic, P2(1)2(1)2(1), a = 7.233(2) Å, b = 15.159(4) Å, c = 25.591(7) Å, Z = 4. The manganese derivative exhibits an efficiency 8 times that of urea in second-harmonic generation at 1.9mgr;m. INDO/SCI-SOS quantum-chemical calculations predict a sizable molecular nonlinear response and an enhancement of the nonlinearity after metal complexation.

Published
2001

44. Stilbazolium-MPS3 Nanocomposites with Large Second-Order Optical Nonlinearity and Permanent Magnetization

Author

Isabelle Ledoux, Pascal G. Lacroix, René Clément, Keitaro Nakatani, and Joseph Zyss

Subjects
Magnetization, Multidisciplinary, Nanocomposite, chemistry, Inorganic chemistry, Poling, Intercalation (chemistry), Analytical chemistry, Second-harmonic generation, chemistry.chemical_element, Nonlinear optics, Manganese, Ion
Abstract

Intercalated layered materials comprising an organic dye and inorganic MPS(3) [where M is either the manganese ion (Mn(2+)) or the cadmium ion (Cd(2+))] phases have been prepared. The intercalation process induces a spontaneous poling, giving rise to an efficiency of 750 times that of urea in second-harmonic generation for the cadmium derivative. In addition, the manganese derivative displays a permanent magnetization below 40 kelvin. Thus, these materials exhibit both a large optical nonlinearity and magnetic ordering.

Published
1994

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