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Thioether polymers are fundamental for a variety of applications. Their synthesis is, however, more challenging than that of other metal-catalyzed reactions due to the reported detachment of the S atom during thermal activation. In this study, it has been demonstrated unambiguously that thermal annealing results in the thioetherification of the 4-bromo-4-mercaptobiphenyl molecule (Br-MBP) adsorbed on the surface of Au(111). Through complementary techniques, such as scanning tunneling microscopy, spectroscopy, and first-principle calculations, we have identified four reaction steps, involving sulfhydryl or bromine molecular functional groups and leading to the formation of intermolecular C–S bonds. To form the thioether polymer and to overcome the competitive formation of C–C bonds, two reaction steps, the dehalogenation, and dissociation of the S–Au bond, must occur simultaneously. We detail the electronic properties of the phenyl–sulfur bond and the polymer as a function of the ligand length. This result suggests a wider perspective of this chemical synthesis., L.V. acknowledges the funding of Diputación Foral de Guipuzcoa (Red/Sarea 2021-CIEN-000032-01, Red/Sarea 2022-CIEN-000017-01), the Basque Government (Proyectos de Investigación Básica y/o Aplicada grant number PIBA-2021-0026, and Grupo consolidado IT1453-22. R.R. and N.L. acknowledge financial support from the Spanish State Research Agency Grant PID2021-127917NB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”; from the European Union project ESiM 101046364; and they are grateful for the computer resources at Finisterrae II, and the technical support provided by CESGA.

Strain is an effective strategy to modulate the optoelectronic properties of 2D materials, but it has been almost unexplored in layered hybrid organic–inorganic metal halide perovskites (HOIPs) due to their complex band structure and mechanical properties. Here, we investigate the temperature-dependent microphotoluminescence (PL) of 2D (C6H5CH2CH2NH3)2Cs3Pb4Br13 HOIP subject to biaxial strain induced by a SiO2 ring platform on which flakes are placed by viscoelastic stamping. At 80 K, we found that a strain of, This work is supported by the Spanish MICINN under Project PID2019-108153GA-I00 and under the María de Maeztu Units of Excellence Programme (MDM-2016-0618). B.M-G. thanks Gipuzkoa Council (Spain) in the frame of Gipuzkoa Fellows Program and to Prof. A. Mateo-Alonso (Molecular and Supramolecular Materials Group - POLYMAT) for the access to the Chemistry Lab to grow the crystals. M.G. acknowledges support from la Caixa Foundation (ID 0010434) for a Junior Leader fellowship (Grant No. LCF/BQ/PI19/11690017).

Non-covalent bonds are fundamental for designing self-assembled organic structures with potentially high responsiveness to mechanical, light, and thermal stimuli. The weak intermolecular interaction allows triggering charge-transport, energy-conversion, enzymatic, and catalytic activity, to name a few. Here, we discuss the synergistic action that multiple highly-directional and purely electrostatic bonds have in assembling one molecular specie, namely 4,7-dibromobenzo[c]-1,2,5-thiadiazole (2Br-BTD), in two different patterns on the Au(111) surface. We find, using scanning tunneling microscopy (STM) and density functional theory (DFT), that multiple secondary-interactions strengthen the electrostatic attraction between the pnicogen and chalcogen atoms forming [S–N]2 heterocycles, the building block of the two networks. Among these interactions, there are halogen–halogen bonds that form characteristic supra-molecular synthons of 3, 4, or 6 molecules. However, not all these nodal structures contribute to the cohesion of the system. In such cases, other secondary bonds involving hydrogen or nitrogen compensate for the eventual deficiency., We acknowledge the funding of Diputación Foral de Guipuzcoa (Red/Sarea 2021-CIEN-000032-01, Red/Sarea 2022-CIEN-000017-01), the Basque Government (Proyectos de Investigación Básica y/o Aplicada grant number PIBA-2021-0026 and Grupo consolidado IT1453-22.) and the Spanish State Research Agency PID2019-107338RB-C66).

The condensed phases of the carbon-based nanobowl corannulene are herein investigated in the temperature range 200–573 K, combining differential scanning calorimetry, synchrotron X-ray diffraction, and quasielastic neutron-scattering. For the first time, we identify the presence of a well-defined thermal event at 382 K, a figure well below a melting point of 540 K. Contrary to naïve expectation, detailed analysis of the neutron-scattering data below and above this pre-melting transition signals the emergence of correlated stochastic dynamics within both thermodynamically stable solid phases of the material. We find that these are progressively responsible for the suppression of molecular and supramolecular order over mesoscopic length scales, and are associated with the formation of high-symmetry rotor-like states exhibiting localized stochastic motions. Upon cooling from the melt, we have also discovered a robust hysteresis associated with the existence of hitherto-unknown metastable liquid (deep-supercooled) and disordered-solid phases. This behaviour is markedly different from that observed in the quintessential Buckminsterfullerene C60 or other chemically substituted fullerene adducts studied to date at this level of detail. These results evince new and yet-to-tapped opportunities for the use of the stable and metastable phases of carbon-based nanobowls in novel applications exploiting the emergence of dynamical disorder at the nanoscale., This work has received support from the Gipuzkoako Foru Aldundia and the Spanish Ministry of Science and Innovation under Grant Numbers 2020-CIEN-000009-01 and PID2020-114506 GB-I00, respectively.

Helicity preserving nanostructures and metasurfaces have been recently proposed as suitable candidates to enhance spectroscopic features of chiral molecules. With this in mind, we highlight that losses in the constituent nonmagnetic materials dramatically affect the possibility of constructing structures which conserve helicity. We first present a general procedure that permits the evaluation of the normalized helicity expectation value, hLiN, i.e. the observable that allows for the identification of helicity preserving scatterers. We then apply this procedure to the case of a chiral sphere, which in an orientation averaged picture can capture the optical response of chiral inorganic nanostructures, obtaining a widely applicable analytical expression of Image hLiN. Finally, we numerically show that optical losses impose an upper bound to the helicity expectation value on nonmagnetic core–shells and chiral spheres., J. L. A., J. O. T. and A. G. E. acknowledge support from the Spanish Ministerio de Ciencia e Innovación (PID2019-109905GA-C2) and from Eusko Jaurlaritza (IT1164-19 and KK-2021/00082). A. G. E. acknowledges funding from Programa Red Guipuzcoana de Ciencia, Tecnología e Innovación 2021 (Grant Nr. 2021-CIEN-000070-01. Gipuzkoa Next). A. G. E. and G. M. T. acknowledge funding from the Basque Government's IKUR initiative on Quantum technologies (Department of Education).

Atomically thin van der Waals magnetic crystals are characterized by tunable magnetic properties related to their low dimensionality. While electrostatic gating has been used to tailor their magnetic response, chemical approaches like intercalation remain largely unexplored. Here, we demonstrate the manipulation of the magnetism in the van der Waals antiferromagnet NiPS3 through the intercalation of different organic cations, inserted using an engineered two-step process. First, the electrochemical intercalation of tetrabutylammonium cations (TBA+) results in a ferrimagnetic hybrid compound displaying a transition temperature of 78 K, and characterized by a hysteretic behavior with finite remanence and coercivity. Then, TBA+ cations are replaced by cobaltocenium via an ion-exchange process, yielding a ferrimagnetic phase with higher transition temperature (98 K) and higher remanent magnetization. Importantly, we demonstrate that the intercalation and cation exchange processes can be carried out in bulk crystals and few-layer flakes, opening the way to the integration of intercalated magnetic materials in devices., The authors acknowledge R. Llopis and A. Eleta for technical support. This work is supported by “la Caixa” Foundation (ID 100010434), under the agreement LCF/BQ/PI19/11690017, by the Spanish MICINN under Project PID2019-108153GA-I00, RTI2018-094861-B-100 and under the María de Maeztu Units of Excellence Program (MDM-2016-0618). B. M.-G. thanks Gipuzkoa Council (Spain) in the frame of Gipuzkoa Fellows Program.

Chiral materials are an ideal playground for exploring the relation between symmetry, relativistic effects and electronic transport. For instance, chiral organic molecules have been intensively studied to electrically generate spin-polarized currents in the last decade, but their poor electronic conductivity limits their potential for applications. Conversely, chiral inorganic materials such as tellurium have excellent electrical conductivity, but their potential for enabling the electrical control of spin polarization in devices remains unclear. Here, we demonstrate the all-electrical generation, manipulation and detection of spin polarization in chiral single-crystalline tellurium nanowires. By recording a large (up to 7%) and chirality-dependent unidirectional magnetoresistance, we show that the orientation of the electrically generated spin polarization is determined by the nanowire handedness and uniquely follows the current direction, while its magnitude can be manipulated by an electrostatic gate. Our results pave the way for the development of magnet-free chirality-based spintronic devices., This work is supported by the Spanish Ministerio de Ciencia e Innovación (MICINN) under projects RTI2018-094861-B-100 and PID2019-108153GA-I00 and under the Maria de Maeztu Units of Excellence Programme (MDM-2016-0618); by the European Union Horizon 2020 under the Marie Slodowska-Curie Actions (0766025-QuESTech and 892983-SPECTER); and by Intel Corporation under ‘FEINMAN’ and ‘VALLEYTRONICS’ Intel Science Technology Centers. B.M.-G. acknowledges support from the Gipuzkoa Council (Spain) in the frame of the Gipuzkoa Fellows Program. M.S.-R. acknowledges support from La Caixa Foundation (no. 100010434) with code LCF/BQ/DR21/11880030. M.G. acknowledges support from La Caixa Foundation (no. 100010434) for a Junior Leader fellowship (grant no. LCF/BQ/PI19/11690017). A.J. acknowledges support from CRC/TRR 227 of Deutsche Forschungsgemeinschaft.

The vibrational dynamics of pure and methylammonium-doped formamidinium lead iodide perovskites (FAPbI3) has been investigated by high-resolution neutron spectroscopy. For the first time, we provide an exhaustive and accurate analysis of the cation vibrations and underlying local structure around the organic moiety in these materials using first-principles electronic-structure calculations validated by the neutron data. Inelastic neutron scattering experiments on FAPbI3 provide direct evidence of the formation of a low-temperature orientational glass, unveiling the physicochemical origin of phase metastability in the tetragonal structure. Further analysis of these data provides a suitable starting point to explore and understand the stabilization of the perovskite framework via doping with small amounts of organic cations. In particular, we find that the hydrogen-bonding interactions around the formamidinium cations are strengthened as a result of cage deformation. This synergistic effect across perovskite cages is accompanied by a concomitant weakening of the methylammonium interactions with the surrounding framework., K.D. and F.F.A. gratefully acknowledge financial support from the Gipuzkoako Foru Aldundia under grant no. 2020-CIEN-000009-01. This work has been supported by PL-Grid Infrastructure and the PROMETHEUS facility. M.K. is grateful for financial support from the Swedish Research Council (2016-06258).

The exfoliation of layered magnetic materials generates atomically thin flakes characterized by an ultrahigh surface sensitivity, which makes their magnetic properties tunable via external stimuli, such as electrostatic gating and proximity effects. Another powerful approach to engineer magnetic materials is molecular functionalization, generating hybrid interfaces with tailored magnetic interactions, called spinterfaces. However, spinterface effects have not yet been explored on layered magnetic materials. Here, the emergence of spinterface effects is demonstrated at the interface between flakes of the prototypical layered magnetic metal Fe3GeTe2 and thin films of Co-phthalocyanine. Magnetotransport measurements show that the molecular layer induces a magnetic exchange bias in Fe3GeTe2, indicating that the unpaired spins in Co-phthalocyanine develop antiferromagnetic ordering and pin the magnetization reversal of Fe3GeTe2 via magnetic proximity. The effect is strongest for a Fe3GeTe2 thickness of 20 nm, for which the exchange bias field reaches −840 Oe at 10 K and is measurable up to ≈110 K. This value compares very favorably with previous exchange bias fields reported for Fe3GeTe2 in all-inorganic van der Waals heterostructures, demonstrating the potential of molecular functionalization to tailor the magnetism of van der Waals layered materials., This work was supported by “la Caixa” Foundation (ID 100010434), under the agreement LCF/BQ/PI19/11690017, by the Spanish MICINN under Project PID2019-108153GA-I00, RTI2018-094861-B-100 and under the María de Maeztu Units of Excellence Program (MDM-2016-0618). This work was also supported by the FLAG-ERA grant MULTISPIN, by the Spanish MCIN/AEI with grant number PCI2021-122038-2A. B.M.-G. thanks Gipuzkoa Council (Spain) in the frame of Gipuzkoa Fellows Program. J.J. acknowledges the support of Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2020R1A6A3A03039086).

We report the formation of five novel multifunctional coordination polymers based on 1H-indazole-4- carboxylic acid (HL). To the best of our knowledge, these complexes are the first examples of coordination compounds constructed with this interesting ligand. These materials were synthesized by solvothermal routes, possess different 2D-structures and show interesting magnetic properties due to the copper compound showing an unusual spin-canted effect while the anisotropic cobalt material behaves as a fieldinduced single molecule magnet. MTT assays performed on human embryonic kidney (HEK293) and mouse skin melanoma (B16-F10) cell lines indicated that the Cd-based compound was the only one exhibiting dose-dependent toxicity on B16-F10 cells, most likely due to the release of toxic Cd(II). Cadmium and zinc polymers exhibit interesting luminescence properties. The fact that zinc polymers did not exhibit inherent toxicity against both cancer and non-cancerous cells make this new family an excellent candidate for further investigation in the field of luminescent materials with biomedical applications., Junta de Andalucia FQM-394 FQM-1484, Red Guipuzcoana de Ciencia, Tecnologia e Innovacion OF218/2018, University of Basque Country GIU 17/13, Basque Government IT1005-16, Spanish Ministry of Science, Innovation and Universities (MCIU/AEI/FEDER, UE) PGC2018-102052-A-C22 PGC2018-102052-B-C21, European Union (EU), ESF, Government of the Basque Country, FEDER/MCIU/AEI RYC-2016-21042 JdC-2017

Plasmonic multinanoparticle systems exhibit collective electric and magnetic resonances that are fundamental for the development of state-of-the-art optical nanoantennas, metamaterials, and surface-enhanced spectroscopy substrates. While electric dipolar modes have been investigated in both the classical and quantum realm, little attention has been given to magnetic and other “dark” modes at the smallest dimensions. Here, we study the collective electric, magnetic, and dark modes of colloidally synthesized silver nanosphere trimers with varying interparticle separation using scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS). This technique enables direct visualization and spatially selective excitation of individual trimers, as well as manipulation of the interparticle distance into the subnanometer regime with the electron beam. Our experiments reveal that bonding electric and magnetic modes are significantly impacted by quantum effects, exhibiting a relative blueshift and reduced EELS amplitude compared to classical predictions. In contrast, the trimer’s electric dark mode is not affected by quantum tunneling for even Ångström-scale interparticle separations. We employ a quantum-corrected model to simulate the effect of electron tunneling in the trimer which shows excellent agreement with experimental results. This understanding of classical and quantum-influenced hybridized modes may impact the development of future quantum plasmonic materials and devices, including Fano-like molecular sensors and quantum metamaterials., A.G.-E., G.A., R.E., and J.A acknowledge project FIS2013-41184-P of the Spanish Ministry of Economy and Competitiveness. J.A.S. and J.A.D. acknowledge funding from a Presidential Early Career Award administered through the Air Force Office of Scientific Research (FA9550-15-1-0006), as well as funding from a National Science Foundation CAREER Award (DMR-1151231). Electron spectroscopy was partially supported by the DOE ‘Light-Material Interactions in Energy Conversion’ Energy Frontier Research Center under Grant DESC0001293. A.G.-E. and R.E. received funding from the Fellows Gipuzkoa fellowship of the Gipuzkoako Foru Aldundia through the FEDER “Una Manera de hacer Europa”.

arXiv:1509.03851v3, Plasmon-enhanced Raman scattering can push single-molecule vibrational spectroscopy beyond a regime addressable by classical electrodynamics. We employ a quantum electrodynamics (QED) description of the coherent interaction of plasmons and molecular vibrations that reveal the emergence of nonlinearities in the inelastic response of the system. For realistic situations, we predict the onset of phonon-stimulated Raman scattering and a counterintuitive dependence of the anti-Stokes emission on the frequency of excitation. We further show that this QED framework opens a venue to analyze the correlations of photons emitted from a plasmonic cavity., M.K.S., R.E., and J.A. acknowledge funding from the project FIS2013-41184-P of the Spanish Ministry of Economy and Competitiveness, the ETORTEK IE14-393 NANOGUNE’14 project of the Department of Industry of the Government of the Basque Country, project IT756-13 of the Department of Education and Culture of the Basque Country, scholarship AP-2012-4204 from the Spanish Ministry of Education, Culture and Sport, financial assistance award 70NANB15H32 from U.S. Department of Commerce, National Institute of Standards and Technology, and the Fellows Gipuzkoa program of the Gipuzkoako Foru Aldundia through the FEDER funding scheme of the European Union, Una manera de hacer Europa. A.G.T. acknowledges support from the IntraEuropean Fellowship NanoQuIS (625955).

arXiv:1512.02104v2, We present a study of the optical response of compact and hollow icosahedral clusters containing up to 868 silver atoms by means of time-dependent density functional theory. We have studied the dependence on size and morphology of both the sharp plasmonic resonance at 3–4 eV (originated mainly from sp-electrons), and the less studied broader feature appearing in the 6–7 eV range (interband transitions). An analysis of the effect of structural relaxations, as well as the choice of exchange correlation functional (local density versus generalised gradient approximations) both in the ground state and optical response calculations is also presented. We have further analysed the role of the different atom layers (surface versus inner layers) and the different orbital symmetries on the absorption cross-section for energies up to 8 eV. We have also studied the dependence on the number of atom layers in hollow structures. Shells formed by a single layer of atoms show a pronounced red shift of the main plasmon resonances that, however, rapidly converge to those of the compact structures as the number of layers is increased. The methods used to obtain these results are also carefully discussed. Our methodology is based on the use of localised basis (atomic orbitals, and atom-centered and dominant-product functions), which bring several computational advantages related to their relatively small size and the sparsity of the resulting matrices. Furthermore, the use of basis sets of atomic orbitals also allows the possibility of extending some of the standard population analysis tools (e.g. Mulliken population analysis) to the realm of optical excitations. Some examples of these analyses are described in the present work., This work is supported, in part, by the ORGAVOLT (ORGAnic solar cell VOLTage by numerical computation) Grant ANR-12-MONU-0014-02 of the French Agence Nationale de la Recherche (ANR) 2012 Programme Modèles Numériques. F Marchesin, P Koval and D Sánchez-Portal acknowledge support from the Deutsche Forschungsgemeinschaft (DFG) through the sfb1083 project, the Spanish mineco MAT2013-46593-C6-2-P project, the Euroregion Aquitaine-Euskadi program and from the Basque Departamento de Educación, upv/ehu (Grant No. IT-756-13). Peter Koval acknowledges financial support from the Fellows Gipuzkoa program of the Gipuzkoako Foru Aldundia through the FEDER funding scheme of the European Union.

Carbon nanotubes, gold nanorods, and silver nanoparticles can be transferred from water to organic solvents and back to water again by using polymeric ionic liquids (PILs) as vehicles (see scheme). The PILs are able to trap several nano-objects during their anion-exchange-induced precipitation in water. This reversible process provides a PIL/nano-object composite that is fully redispersible in organic solvents., This work was funded by the Diputación of Gipuzkoa and the Basque Government.