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Carbon dioxide (CO2) is widespread in astrochemically relevant environments, often coexisting with water (H2O) ices and thus triggering a great interest regarding the possible formation of their adducts under various thermodynamic conditions. Amongst them, solid carbonic acid (H2CO3) remains elusive, yet being widely studied. Synthetic routes followed for its production have always been characterised by drastic irradiation on solid ice mixtures or complex procedures on fluid samples (such as laser heating at moderate to high pressures). Here we report about a simpler yet effective synthetic route to obtain two diverse carbonic acid crystal structures from the fast, cold compression of pristine clathrate hydrate samples. The two distinct polymorphs we obtained, differing in the water content, have been deeply characterised via spectroscopic and structural techniques to assess their composition and their astonishing pressure stability, checked up to half a megabar, also highlighting the complex correlations between them so to compile a detailed phase diagram of this system. These results may have a profound impact on the prediction and modelisation of the complex chemistry which characterises many icy bodies of our Solar System. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is widespread in astrochemically relevant environments, often coexisting with water (H2O) ices and thus triggering a great interest regarding the possible formation of their adducts under various thermodynamic conditions. Amongst them, solid carbonic acid (H2CO3) remains elusive, yet being widely studied. Synthetic routes followed for its production have always been characterised by drastic irradiation on solid ice mixtures or complex procedures on fluid samples (such as laser heating at moderate to high pressures). Here we report about a simpler yet effective synthetic route to obtain two diverse carbonic acid crystal structures from the fast, cold compression of pristine clathrate hydrate samples. The two distinct polymorphs we obtained, differing in the water content, have been deeply characterised via spectroscopic and structural techniques to assess their composition and their astonishing pressure stability, checked up to half a megabar, also highlighting the complex correlations between them so to compile a detailed phase diagram of this system. These results may have a profound impact on the prediction and modelisation of the complex chemistry which characterises many icy bodies of our Solar System. [ABSTRACT FROM AUTHOR]

Several Ba−Li−Ge ternary phases are known and structurally characterized, including the title compound Ba2LiGe3. Its structure is reported to contain [Ge6]10− anions that exhibit delocalized bonding with a Hückel‐like aromatic character. The Ge atoms are in the same plane with the Li atoms, and if both types of atoms are considered as covalently bonded, [LiGe3]4− honeycomb‐like layers will result. The latter are separated by slabs of Ba2+ cations. However, based on the systematic work detailed herein, it is necessary to re‐evaluate the phase as Ba2Li1−xGe3+x (x<0.05). Although small, the homogeneity range is clearly demonstrated in the gradual change of the unit cell for four independent samples. Subsequent characterization by single‐crystal X‐ray diffraction methods shows that the Ba2Li1−xGe3+x structure, responds to the varied number of valence electrons and the changes are most pronounced for the refined lengths of the Li−Ge and Ge−Ge bonds. Indirectly, the changes in the Ge−Li/Ge distances within layers affect the stacking too, and these changes can be correlated to the variation of the c‐cell parameter. Chemical bonding analysis based on TB‐LMTO‐ASA level calculations affirms the notion for covalent character of the Ge−Ge bonds; the Ba−Ge and Li−Ge interactions also show some degree of covalency. [ABSTRACT FROM AUTHOR]

This invited Team Profile was created by the Laboratory of Advanced Functional Materials (Tokoro Lab), Division of Materials Science, Faculty of Pure and Applied Sciences, University of Tsukuba (Japan); the Multifunctional Luminescent Materials Group (Szymon Group, MLMG), Faculty of Chemistry, Jagiellonian University, Kraków (Poland); and the Solid State Physical Chemistry Group (Ohkoshi Lab), Department of Chemistry, School of Science, The University of Tokyo (Japan). They recently published an article on a bimetallic cyanido‐bridged TbIII−CoIII framework exhibiting a desolvation‐induced structural transformation providing high‐symmetry trigonal‐prismatic [TbIII(NC)6]3− complexes. This induces a strong magnetic anisotropy leading to single‐molecule magnet behavior with an energy barrier of 854(26) K, which appears in the cryogenic temperatures range, together with the concomitant luminescent thermometry effect. "Desolvation‐Induced Highly Symmetrical Terbium(III) Single‐Molecule Magnet Exhibiting Luminescent Self‐Monitoring of Temperature", J. Wang, J. J. Zakrzewski, M. Zychowicz, Y. Xin, H. Tokoro, S. Chorazy, S. Ohkoshi, Angew. Chem. Int. Ed. 2023, 62, e202306372. [ABSTRACT FROM AUTHOR]

This invited Team Profile was created by the Laboratory of Advanced Functional Materials (Tokoro Lab), Division of Materials Science, Faculty of Pure and Applied Sciences, University of Tsukuba (Japan); the Multifunctional Luminescent Materials Group (Szymon Group, MLMG), Faculty of Chemistry, Jagiellonian University, Kraków (Poland); and the Solid State Physical Chemistry Group (Ohkoshi Lab), Department of Chemistry, School of Science, The University of Tokyo (Japan). They recently published an article on a bimetallic cyanido‐bridged TbIII−CoIII framework exhibiting a desolvation‐induced structural transformation providing high‐symmetry trigonal‐prismatic [TbIII(NC)6]3− complexes. This induces a strong magnetic anisotropy leading to single‐molecule magnet behavior with an energy barrier of 854(26) K, which appears in the cryogenic temperatures range, together with the concomitant luminescent thermometry effect. "Desolvation‐Induced Highly Symmetrical Terbium(III) Single‐Molecule Magnet Exhibiting Luminescent Self‐Monitoring of Temperature", J. Wang, J. J. Zakrzewski, M. Zychowicz, Y. Xin, H. Tokoro, S. Chorazy, S. Ohkoshi, Angew. Chem. Int. Ed. 2023, 62, e202306372. [ABSTRACT FROM AUTHOR]

The article focuses on the synthesis and characterization of a high-entropy oxide (HEO) called Iron(II) Oxide (FeO)-HEO, which contains divalent Manganese (Mn) and Iron (Fe) in a rocksalt crystal structure. Topics include the concept of HEOs and their unique compositional features, the challenge of introducing divalent Mn(II) and Fe(II) into a rocksalt HEO, and the phase stability of FeO-HEO under different conditions.

In the industrial production of molybdenum the reduction of molybdenum trioxide with hydrogen is a two‐step process. In order to get a deeper understanding of the chemistry involved, in situ studies were performed on the thermal behavior of molybdenum trioxide and the first reduction step to molybdenum dioxide. MoO3 shows a very strong anisotropy for thermal expansion (linear expansion coefficients α in 10−4 K−1: 1.32(4) for a, 5.5(1) for b, −0.246(5) for c). Upon heating in air, preferred orientation in XRPD patterns decreases and the color changes from grey to yellow, probably caused by decreasing oxygen vacancy concentration. The reduction of MoO3 by hydrogen was investigated via in situ X‐ray powder diffraction for varying heating rate, hydrogen flow and potassium content. The formation of the intermediate γ‐Mo4O11 shows a higher rate for increasing potassium content; it does not play a role whether potassium is present in the starting material MoO3 or in MoO2 formed in the reaction. The high‐temperature modification of K2MoO4 was found to crystallize in the α‐K2SO4 type (P63/mmc, a=6.3463(2) Å, c= 8.1331(2) Å). Heating up MoO3 in vacuum (1 Pa) with the same T,t protocol as above yields MoO2 even without the presence of hydrogen. [ABSTRACT FROM AUTHOR]

In this work, intra- and intermolecular halogen and chalcogen bonds (HlgBs and ChBs, respectively) present in the solid state of nucleic acids (NAs) have been studied at the RI-MP2/def2-TZVP level of theory. To achieve this, a Protein Data Bank (PDB) survey was carried out, revealing a series of structures in which Br/I or S/Se/Te atoms belonging to nucleobases or pentose rings were involved in noncovalent interactions (NCIs) with electron-rich species. The energetics and directionality of these NCIs were rationalized through a computational study, which included the use of Molecular Electrostatic Potential (MEP) surfaces, the Quantum Theory of Atoms in Molecules (QTAIM), and Non Covalent Interaction plot (NCIplot) and Natural Bonding Orbital (NBO) techniques. [ABSTRACT FROM AUTHOR]

Effective Hamiltonian of Crystal Field (EHCF) is a hybrid quantum chemical method originally developed for an accurate treatment of highly correlated d-shells in molecular complexes of transition metals. In the present work, we generalise the EHCF method to periodic systems containing transition metal atoms with isolated d-shells, either as a part of their crystal structure or as point defects. A general solution is achieved by expressing the effective resonance interactions of an isolated d-shell with the band structure of the crystal in terms of the Green's functions represented in the basis of local atomic orbitals. Such representation can be obtained for perfect crystals and for periodic systems containing atomic scale defects. Our test results for transition metal oxides (MnO, FeO, CoO, and NiO) and MgO periodic solid containing transition metal impurities demonstrate the ability of the EHCF method to accurately reproduce the spin multiplicity and spatial symmetry of the ground state. For the studied materials, these results are in a good agreement with experimentally observed d-d transitions in optical spectra. The proposed method is discussed in the context of modern solid state quantum chemistry and physics. [ABSTRACT FROM AUTHOR]

I "Poor is the pupil who does not surpass his master" i Leonardo da Vinci At the beginning of 2023, during a celebration in Elche, Spain, there were a number of talks by mostly scientists formerly associated with our research group. When it came time for Maurizio to do research on particular addition reaction to fullerene C SB 60 sb , I mentioned to him that someone in the group, unfortunately I do not remember who, had successfully added tosyl azide to fullerene C SB 60 sb . Maurizio, after his move to Trieste, has shown that the reaction is applicable to other nanocarbons, so it is, indeed, a reaction of universal applicability to nanocarbons.[12] But Maurizio did not bask in the glory of this achievement. [Extracted from the article]

Prof. Lin was a world-class researcher, and a charismatic and accomplished academician with a remarkable record, holding 12 academic positions across 7 academic institutions, winning 16 honors and awards, publishing more than 30 books, over 850 peer-reviewed scientific publications, and boasting over 150 collaborators. I am grateful to Prof. Lin for his kindness to accept me as a postdoctoral researcher at Institute of Atomic and Molecular Sciences, Academia Sinica through Prof. Ohtsuki's introduction, even though I was unemployed after completing the doctoral course. Professor Lin had close ties with Xiamen University since 1990s when he became a good friend of the late Professor Qianer Zhang. I Dr. Ling Yang (School of Chemistry and Chemical Engineering, Harbin Institute of Technology) i I As a Ph.D. student of Prof. Sheng-Hsien Lin's lab, we remember Prof. Lin as a clear, rigorous mentor who always gave us precious inspiration and helped us clarify many complex systems in the fields of physical and analytical chemistry i . [Extracted from the article]

Zinc oxide (ZnO) tetrapods as microparticles with nanostructured surfaces show peculiar physical properties and anti-infective activities. The aim of this study was to investigate the antibacterial and bactericidal properties of ZnO tetrapods in comparison to spherical, unstructured ZnO particles. Additionally, killing rates of either methylene blue-treated or untreated tetrapods and spherical ZnO particles for Gram-negative and Gram-positive bacteria species were determined. ZnO tetrapods showed considerable bactericidal activity against Staphylococcus aureus, and Klebsiella pneumoniae isolates, including multi-resistant strains, while Pseudomonas aeruginosa and Enterococcus faecalis remained unaffected. Almost complete elimination was reached after 24 h for Staphylococcus aureus at 0.5 mg/mL and Klebsiella pneumoniae at 0.25 mg/mL. Surface modifications of spherical ZnO particles by treatment with methylene blue even improved the antibacterial activity against Staphylococcus aureus. Nanostructured surfaces of ZnO particles provide active and modifiable interfaces for the contact with and killing of bacteria. The application of solid state chemistry, i.e., the direct matter-to-matter interaction between active agent and bacterium, in the form of ZnO tetrapods and non-soluble ZnO particles, can add an additional principle to the spectrum of antibacterial mechanisms, which is, in contrast to soluble antibiotics, depending on the direct local contact with the microorganisms on tissue or material surfaces. [ABSTRACT FROM AUTHOR]

The nascent field of computationally aided molecular design will be built around the ability to make computation useful to synthetic chemists who draw on their empirically based chemical intuition to synthesize new and useful molecules. This fact poses a dilemma, as much of existing chemical intuition is framed in the language of chemical bonds, which are pictured as possessing physical properties. Unfortunately, it has been posited that calculating these bond properties is impossible because chemical bonds do not exist. For much of the computationalchemistry community, bonds are seen as mythical—the unicorns of the chemical world. Here, we show that this is not the case. Using the same formalism and concepts that illuminated the atoms in molecules, we shine light on the bonds that connect them. The real space analogue of the chemical bond becomes the bond bundle in an extended quantum theory of atoms in molecules (QTAIM). We show that bond bundles possess all the properties typically associated with chemical bonds, including an energy and electron count. In addition, bond bundles are characterized by a number of nontraditional attributes, including, significantly, a boundary. We show, with examples drawn from solid state and molecular chemistry, that the calculated properties of bond bundles are consistent with those that nourish chemical intuition. We go further, however, and show that bond bundles provide new and quantifiable insights into the structure and properties of molecules and materials. [ABSTRACT FROM AUTHOR]

Rhenium powder is industrially produced in a two‐step reaction by reducing NH4ReO4 with hydrogen at 623 and 1173 K. In this study, both steps of the production process have been investigated via in situ X‐ray powder diffraction. Up to 550 K no reaction with hydrogen can be observed. Between 550 K and 623 K poorly crystalline rhenium is formed. Crystallinity is increased during the second step at 1173 K. Annealing under hydrogen or nitrogen provides a comparable product in respect to the examined crystal and real structure parameters independent of the gas atmosphere. [ABSTRACT FROM AUTHOR]

Metallogeny is the science of ore and mineral deposit formation in geological space and time. Metallogeny is interdisciplinary by nature, comprising elements of natural science disciplines such as planetology to solid state physics and chemistry, and volcanology. It is the experimental forefront of research and bold thinking, based on an ever-growing foundation of solid knowledge. Therefore, metallogeny is not a closed system of knowledge but a fast-growing assemblage of structured and unstructured information in perpetual flux. This paper intends to review its current state and trends. The latter may introduce speculation and fuzziness. Metallogeny has existed for over 100 years as a branch of Earth Science. From the discovery of plate tectonics (ca. 1950) to the end of the last century, metallogeny passed through a worldwide phase of formally published 'metallogenetic' maps. In the last decades, a rapidly growing number of scientists, digitization and splendid new tools fundamentally boosted research. More innovations may be expected by the growing use of an evolving systematic 'Geodata Science' for metallogenic research by an increasingly global human talent pool. Future requirements for metallic and mineral raw materials, especially the critical natural elements and compounds that are needed for the nascent carbon-free economy, already drive activities on stock markets and in the resource industry. State geological surveys, academia and private companies embrace the challenges. The new age requires intensified metallogenic backing. In this paper, principles of metallogeny are recalled concerning concepts and terms. A metallogenic classification of ore and mineral deposits is proposed, and the intimate relations of metallogenesis with geodynamics are sketched (ancient lid tectonics and modern plate tectonics). Metallogenic models assemble a great diversity of data that allow an ever better understanding of ore formation, foremost by illuminating the geological source-to-trap migration of ore metals, the petrogenetic and geodynamic–tectonic setting, the spatial architecture of ore deposits and the nature and precise timing of involved processes. Applied metallogeny allows companies to choose strategy and tactics for exploration investment and for planning the work. Based on comprehensive metallogenic knowledge, mineral system analysis (MSA) selects those elements of complex metallogenic models, which are detectable and can guide exploration in order to support applications such as mineral prospectivity mapping, mineral potential evaluation and targeting of detailed investigations. MSA founded on metallogenic models can be applied across whole continents, or at the scale of regional greenfield search, or in brownfields at district to camp scale. By delivering the fundamental keys for MSA, supported by unceasing innovative research, the stream of new metallogenic insights is essential for improving endowment estimates and for successful exploration. [ABSTRACT FROM AUTHOR]

The nature of 4f-3d magnetic interaction in oxides as well as its influence on the magnetocaloric effect (MCE) is an interesting topic. Here, we report the weak magnetic interaction and large MCE in a new triangular lattice GdFeTeO6 synthesized by the solid state reaction method. The weak exchange, which was seldom observed in 4f-3d oxides, is supported by the low ordering temperature (TC ≤ 3 K) and a positive but small Curie-Weiss temperature (θp = 3 K). Under an external magnetic field, the magnetization process yields a large magnetic entropy change of 38.5 J kg−1 K−1 at 5 K for 0-7 T and 23.6 J kg−1 K−1 at 3 K for 0-3 T. Finally, our first-principles calculations demonstrate a ferrimagnetic spin model with the Gd(↑)-Gd(↑)-Fe(↓)-Fe(↓) configuration. The weak magnetic interaction is an average effect of ferromagnetic (4f-4f and 3d-3d) and antiferromagnetic (4f-3d) interactions. The antiferromagnetic 4f-3d interaction is a reason for the reduction of MCE. [ABSTRACT FROM AUTHOR]

Lead lanthanum zirconate titanate (PLZT x/59/41) ceramics with x from 0 to 6.5 mol. % are synthesized by the traditional solid-state reaction method. The temperature dependences of dielectric and resonant responses are used to characterize the depolarization processes of poled samples. It is found that the temperature of anti-resonance frequency minima (Tmin-a) accords completely with dielectric loss peak temperature (Tloss). The Tloss instead of anomalous dielectric peak temperature (Td*) can be regarded as depolarization temperature (Td). The Td* deviated from the Tloss suggests that the depolarization process in all the samples includes two stages: domain decoupling and polarization disorientation. With La content increasing, the Tloss decreases and the temperature difference ΔT between Tloss and dielectric peak temperature (Tm) increases nearly linearly. Since all studied samples have similar depolarization and freezing processes and the 0 mol. % La sample behaves like a normal ferroelectric, here we suggest that there may be no essential difference in depolarization process between relaxor and normal ferroelectrics. [ABSTRACT FROM AUTHOR]

Neuromorphic computing and engineering has been the focus of intense research efforts that have been intensified recently by the mutation of Information and Communication Technologies. In fact, new computing solutions and new hardware platforms are expected to emerge to answer to the new needs and challenges of our societies. In this revolution, lots of candidates' technologies are explored and will require leveraging of the pros and cons. In this perspective paper belonging to the special issue on neuromorphic engineering of Journal of Applied Physics, we focus on the current achievements in the field of organic electronics and the potentialities and specificities of this research field. We highlight how unique material features available through organic materials can be used to engineer useful and promising bio-inspired devices and circuits. We also discuss the opportunities that organic electronics offer for future research directions in the neuromorphic engineering field. [ABSTRACT FROM AUTHOR]

We present here a study on the modification of morphological and plasmonic properties of Ag thin films deposited on glass substrates upon annealing in air at different temperatures. Initially, Ag films are continuous and exhibit extended surface plasmons with a resonant absorbance that depends on the film thickness. The dewetting process promotes the formation of nanoparticles with different sizes, shapes, and agglomerations states, besides a partial oxidation from Ag to AgO at surface level. The final Ag-AgO nanostructures are dependent on the annealing temperature and initial film thickness. The optical properties evolve from those typical of metallic films with high reflectivity and extended surface plasmon resonance toward localized surface plasmons characteristic of nanoparticles. The optical evolution and the final plasmonic response are evaluated according to the morphological and structural features of nanostructures. [ABSTRACT FROM AUTHOR]

In contrast to the rapid and revolutionary impact of solution-state Nuclear Magnetic Resonance (NMR) on modern chemistry, the field of solid-state NMR has matured more slowly. This reflects the major technical challenges of much reduced spectral resolution and sensitivity in solid-state as compared to solution-state spectra, as well as the relative complexity of the solid state. In this perspective, we outline the technique developments that have pushed resolution to intrinsic limits and the approaches, including ongoing major developments in the field of Dynamic Nuclear Polarisation, that have enhanced spectral sensitivity. The information on local structure and dynamics that can be obtained using these gains in sensitivity and resolution is illustrated with a diverse range of examples from large biomolecules to energy materials and pharmaceuticals and from both ordered and highly disordered materials. We discuss how parallel developments in quantum chemical calculation, particularly density functional theory, have enabled experimental data to be translated directly into information on local structure and dynamics, giving rise to the developing field of "NMR crystallography." [ABSTRACT FROM AUTHOR]

[Display omitted] Nitrogen and nickel are the main impurities in the type Ib synthetic diamonds obtained under high pressure and high temperature conditions using nickel-containing catalysts. Nitrogen enters the synthesized diamond from the air. The nickel/nitrogen ratio for the two types of diamonds, obtained with and without an aluminum getter that prevents the diamond crystal lattice from nitrogen penetration, was studied by electron spin resonance at 90 K. [ABSTRACT FROM AUTHOR]

In fact, the silver(I) cyanoguanidine nitrate hydrate, Ag(C SB 2 sb N SB 4 sb H SB 4 sb )NO SB 3 sb -½H SB 2 sb O, represents the first example of a monovalent silver complex coordinated through the inner (as opposed to terminal) nitrogen N atoms of the cyanoguanidine ligand. Given that the hydrate was an unexpected product in the intended synthesis of Ag(C SB 2 sb N SB 4 sb H SB 4 sb )NO SB 3 sb , the authors used first principles calculations to demonstrate that bonding through the inner N atom of the ligand is indeed energetically less favourable than coordinating via the terminal atoms. Of course, coordination complexes are not strictly the domain of d-block metals and Jones, Watts and Jones presented a study of alkali metal complexes formed with "super bulky" -diketiminate (Nacnac) ligands [[4]]. Both lithium and potassium complexes were successfully produced, and each was shown to be highly reactive, offering the possibility of using the complexes as reagents themselves for the synthesis of new low-oxidation state metal complexes, which the ligands could stabilise kinetically. [Extracted from the article]

23) can be used to adjust their classical Pauling bond strengths (s SB (IV)Si-O sb Graph: Figure 23 Plot of bond valence vs. bond length for Si-O, Al-O, Na-O, and Zr-O bonds using bond-valence parameters from [44] (from [59]). Bond-valence curves For any pair of bonded atoms, bond valence is inversely proportional to the length of the bond: large bond valences are associated with short bonds, and small bond valences are associated with long bonds. To obtain numerical values for the bond valences, each bond is assigned a bond valence such that the valence-sum rule is satisfied ([34]a): The sum of the bond valences at each atom is equal to the magnitude of the atomic valence. [Extracted from the article]

Six new Schiff based diorganotin(IV) complexes have been synthesized and structurally characterized through multitude analytical techniques. The compound-DNA interaction study has been performed through UV–Visible spectroscopy that revealed high binding potential through a spontaneous process. The complexes have further been investigated for in vitro antimicrobial and anticancer studies. [Display omitted] • Synthesis of six diorganotin(IV) complexes based on two new Schiff base ligands derived by the condensation reaction of aldehydes with acid hydrazides. • Spectroscopic characterization and structural elucidation of all complexes were performed. • Compound-DNA interaction study was performed through UV–Visible spectroscopy. • The compounds were investigated for in vitro antimicrobial studies. • The compounds were evaluated for their anticancer activities. Herein, two Schiff base ligands Ń-(4-diethylamino-2-hydroxybenzylidene) isonicotinohydrazide (L1) and Ń-(2,3-dihydroxybenzylidene) isonicotinohydrazide (L2) and their six di-organotin(IV) complexes (R = C 4 H 9 (1 , 4), C 6 H 5 (2 , 5) and CH 3 (3 , 6)) were synthesized. The solid state and solution chemistry of the ligands and their organotin(IV) complexes was explored through single crystal XRD, FTIR and NMR (1H, 13C and 119Sn) spectroscopy. The single crystal XRD analysis was carried out for complexes 1 , 2 and 5 , reveals the presence square pyramidal, trigonal bipyramidal and pentagonal bipyramidal geometries, respectively. All structures showed distorted geometries because of the constraint offered by five and six membered chelate rings. The results obtained from the interaction study of ligands and complexes with SS-DNA were indicative of high binding potential through a spontaneous process. The results of in vitro antimicrobial studies validated the well-known theory of chelation and overtone concept. Anticancer activities conducted for the ligands and complexes revealed evident anti-proliferative activity of 1 , 2 , 4 and 5 complexes. Complex 2 being the most active one, exhibited pro-apoptotic, cytotoxic effect after PI and DAPI stains. Moreover, after H2DCF-DA staining the treated cancerous cells, an induced oxidative stress was detected. Complexes 2 and 4 also revealed the activation of mitochondrial pathway of apoptosis in treated cancer cells. [ABSTRACT FROM AUTHOR]

ZAAC is an international scientific journal which publishes original papers on new relevant research results from all areas of inorganic chemistry, solid state chemistry, and co‐ordination chemistry.The contributions reflect the latest findings in these research areas and serve the development of new materials, such as super‐hard materials, electrical superconductors, or intermetallic compounds. Up‐to‐date physical methods for the characterization of new chemical compounds and materials are also described... [Extracted from the article]

Synthesis, structure characterization and properties of a new oxidovanadium(IV) coordination polymer incorporating bridging (MoO4)2- and (Mo8O26)4- ligands Keywords: -octamolybdate; bridging ligand; coordination polymer; tetraoxidomolybdate; vanadium EN -octamolybdate bridging ligand coordination polymer tetraoxidomolybdate vanadium 245 252 8 05/13/22 20220501 NES 220501 Dedicated to Professor Christian Näther on the occasion of his 60th birthday. The H atoms attached to the carbon atoms C4, C7, C9, C14, C16, C19, C24, C27, C29 and C30 of the unique terpy ligands function as hydrogen donors while the O atoms O1 and O2 attached to V1 and V2 and the O atoms of the -(Mo SB 8 sb O SB 26 sb ) SP 4- sp unit, viz. Both the unique vanadium V1 and V2 species are bonded to a terminal oxido ligand O1 and O2, respectively, and are further coordinated to a terpy ligand, whose three N atoms span the meridional sites of a {VN SB 3 sb O SB 3 sb } octahedron. [Extracted from the article]

In this study the ability of metal coordinated Chalcogen (Ch) atoms to undergo Chalcogen bonding (ChB) interactions has been evaluated at the PBE0-D3/def2-TZVP level of theory. An initial CSD (Cambridge Structural Database) inspection revealed the presence of square planar Pd/Pt coordination complexes where divalent Ch atoms (Se/Te) were used as ligands. Interestingly, the coordination to the metal center enhanced the σ-hole donor ability of the Ch atom, which participates in ChBs with neighboring units present in the X-ray crystal structure, therefore dictating the solid state architecture. The X-ray analyses were complemented with a computational study (PBE0-D3/def2-TZVP level of theory), which shed light into the strength and directionality of the ChBs studied herein. Owing to the new possibilities that metal coordination offers to enhance or modulate the σ-hole donor ability of Chs, we believe that the findings presented herein are of remarkable importance for supramolecular chemists as well as for those scientists working in the field of solid state chemistry. [ABSTRACT FROM AUTHOR]

An anisotropic atom-atom force-field for pyridine, using distributed atomic multipoles, polarizabilities, and dispersion coefficients and an anisotropic atom-atom repulsion model derived from symmetry-adapted perturbation theory (density functional theory) dimer calculations, is used to model pyridine crystal structures. Here we show that this distributed intermolecular force-field (DIFF) models the experimental crystal structures as accurately as modelling all but the electrostatic term with an isotropic repulsion-dispersion potential that has been fitted to experimental crystal structures. In both cases, the differences are comparable to the changes in the crystal structure with temperature, pressure, or neglect of zero-point vibrational effects. A crystal structure prediction study has been carried out, and the observed polymorphs contrasted with hypothetical thermodynamically competitive crystal structures. The DIFF model was able to identify the structure of an unreported high pressure phase of pyridine, unlike the empirically fitted potential. The DIFF model approach therefore provides a model of the underlying pair potential energy surface that we have transferred to the crystalline phase with a considerable degree of success, though the treatment of the many-body terms needs improvement and the pair potential is slightly over-binding. Furthermore, this study of a system that exhibits isotopic polymorphism highlights that the use of an empirical potential has partially absorbed temperature and zero-point motion effects as well as the intermolecular forces not explicitly represented in the functional form. This study therefore highlights the complexity in modelling crystallization phenomena from a realistic pair potential energy surface. [ABSTRACT FROM AUTHOR]

Magnetic ferroelectrics continue to attract much attention as promising multifunctional materials. Among them, BiFeO3 is distinguished by exceptionally high transition temperatures and, thus, is considered as a prototype room-temperature multiferroic. Since its properties are known to be strongly affected by chemical substitution, recognition of the doping-related factors determining the multiferroic behavior of the material would pave the way towards designing the structures with enhanced magnetoelectric functionality. In this paper, we report on the crystal structure and magnetic and local ferroelectric properties of the Bi1-xPrxFe1xMnxO3 (x≤ 0.3) compounds prepared by a solid state reaction method. The polar R3c structure specific to the parent BiFeO3 has been found to be unstable with respect to doping for x...0.1. Depending on the Pr/Mn concentration, either the antipolar PbZrO3-like or nonpolar PrMnO3-type structure can be observed. It has been shown that the non-ferroelectric compounds are weak ferromagnetic with the remanent/spontaneous magnetization linearly decreasing with an increase in x. The samples containing the polar R3c phase exhibit a mixed antiferromagnetic/weak ferromagnetic behavior. The origin of the magnetic phase separation taking place in the ferroelectric phase is discussed as related to the local, doping introduced structural heterogeneity contributing to the suppression of the cycloidal antiferromagnetic ordering characteristic of the pure BiFeO3. [ABSTRACT FROM AUTHOR]

Phase diagram of FeVO4-CrVO4 solid solutions pertinent with structural and magnetic phases is presented with unambiguous experimental evidences. Solid solutions Fe1–xCrxVO4 (0 ≤ x ≤ 1.0) were synthesized through the standard solid state route and studied by X-ray diffraction, scanning electron microscopy, energy dispersive spectra of X-rays, Raman spectroscopy, d.c. magnetization, and 57Fe Mössbauer spectroscopic studies. FeVO4 and CrVO4 were found to be in triclinic (P-1 space group) and orthorhombic structures (Cmcm space group), respectively. Cr incorporation into the FeVO4 lattice leads to the emergence of a new monoclinic phase dissimilar to the both end members of the solid solutions. In Fe1–xCrxVO4 up to x=0.10, no discernible changes in the triclinic structure were found. A new structural monoclinic phase (C2/m space group) emerges within the triclinic phase at x=0.125, and with the increase in Cr content, it gets stabilized with clear single phase signatures in the range of x=0.175–0.25 as evidenced by the Rietveld analysis of the structures. Beyond x=0.33, orthorhombic phase similar to CrVO4 (Cmcm space group) emerges and coexists with a monoclinic structure up to x=0.85, which finally tends to stabilize in the range of x=0.90–1.00. The Raman spectroscopic studies also confirm the structural transition. FeVO4 Raman spectra show the modes related to three nonequivalent V ions in the triclinic structure, where up to 42 Raman modes are observed in the present study. With the stabilization of structures having higher symmetry, the number of Raman modes decreases and the modes related to symmetry inequivalent sites collate into singular modes from the doublet structure. A systematic crossover from two magnetic transitions in FeVO4, at 21.5K and 15.4K to single magnetic transition in CrVO4, at 71K (antiferromagnetic transition), is observed in magnetization studies. The intermediate solid solution with x=0.15 shows two magnetic transitions, whereas in the compound with x=0.33 one of the magnetic transitions disappears. 57Fe Mössbauer spectroscopic studies show a finger print evidence for disappearance of non-equivalent sites of Fe as the structure changes from Triclinic–Monoclinic–Orthorhombic phases with the increasing Cr content in Fe1–xCrxVO4. Comprehensive studies related to the structural changes in Fe1–xCrxVO4 solid solutions lead us to detailed phase diagrams which shall be characteristic for room temperature structural and temperature dependent magnetic transitions in these solid solutions, respectively. [ABSTRACT FROM AUTHOR]

In this article, we study the spin and tunneling dynamics as a function of magnetic field in a one-dimensional GaAs double quantum dot with both the Dresselhaus and Rashba spin-orbit coupling. In particular, we consider different spatial widths for the spin-up and spin-down electronic states. We find that the spin dynamics is a superposition of slow as well as fast Rabi oscillations. It is found that the Rashba interaction strength as well as the external magnetic field strongly modifies the slow Rabi oscillations which is particularly useful for implementing solid state selective spin transport device. [ABSTRACT FROM AUTHOR]

Thermal properties of a red phosphor CaAlSiN3:Eu (CASN) at elevated temperatures were evaluated. A heat treatment at 800°C degraded the photoluminescence property of CASN and caused irreversible changes in both the excitation and emission intensities. The heat treatment in air simultaneously decreased the N elements and increased the O elements. Consequently, the Eu2+ luminescence center was oxidized and CASN lost its photoluminescence property. Although the crystal structure of CASN host was stable even after the heat treatments, the local structure change around the Eu2+ ions is the origin of the thermal degradation of CASN. We found that the heat treatment in N2 atmosphere suppresses the thermal degradation. This is due to the suppression of N evolutions and the incorporation of O elements, which sustains the optically active Eu2+ state. [ABSTRACT FROM AUTHOR]

We introduce a new fingerprint that allows distinguishing between liquid-like and solid-like atomic environments. This fingerprint is based on an approximate expression for the entropy projected on individual atoms. When combined with local enthalpy, this fingerprint acquires an even finer resolution and it is capable of discriminating between different crystal structures. [ABSTRACT FROM AUTHOR]

Ionically conducting plastic crystals (PCs) are possible candidates for solid-state electrolytes in energy-storage devices. Interestingly, the admixture of larger molecules to the most prominent molecular PC electrolyte, succinonitrile, was shown to drastically enhance its ionic conductivity. Therefore, binary mixtures seem to be a promising way to tune the conductivity of such solid-state electrolytes. However, to elucidate the general mechanisms of ionic charge transport in plastic crystals and the influence of mixing, a much broader database is needed. In the present work, we investigate mixtures of two well-known plastic-crystalline systems, cyclohexanol and cyclooctanol, to which 1 mol.% of Li ions were added. Applying differential scanning calorimetry and dielectric spectroscopy, we present a thorough investigation of the phase behavior and the ionic and dipolar dynamics of this system. All mixtures reveal plastic-crystalline phases with corresponding orientational glass-transitions. Moreover, their conductivity seems to be dominated by the "revolving-door" mechanism, implying a close coupling between the ionic translational and the molecular reorientational dynamics of the surrounding plastic-crystalline matrix. In contrast to succinonitrile-based mixtures, there is no strong variation of this coupling with the mixing ratio. [ABSTRACT FROM AUTHOR]