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Results of a study of the magnetothermoelectric properties and the Shubnikov–de Haas effect in single-crystal wires of various diameters and films based on Bi1–xSbx semimetal alloys have been described. According to the Shubnikov–de Haas oscillations, it has been calculated that the overlap of the L and T bands in the Bi–3at%Sb semimetal wires decreases more than twofold owing to an increase in the antimony concentration. Thermoelectric gap E, the dependence of the gap on wire diameter d, and the temperature dependence of power factor 2(T) as a function of diameter and magnetic field have been calculated. It has been found that a decrease in wire diameter d leads to a semimetal–semiconductor transition at d < 1.2 m, which is more than an order of magnitude higher than in pure Bi wires and 1.5 times higher than in wires of Bi–2at%Sb alloys. It has been shown that thermal gap E increases with decreasing wire diameter d in accordance with a law close to 1/d, which is consistent with theoretical calculations based on the occurrence of the quantum size effect in semimetals. A switching effect in the magnetothermopower has been found; the dependence of this effect on wire diameter d and temperature has been determined. It has been shown that, in a weak magnetic field, the magnetothermopower anisotropy in Bi–3at%Sb wires and films increases with decreasing temperature; this feature can be used in anisotropic thermoelectric energy converters.

The synthesis, characterization, electrochemical performance, and theoretical modeling of two base-metal charge carrier complexes incorporating a pendent quaternary ammonium group, [Ni(bppn-Me3)][BF4], 3', and [Fe(PyTRENMe)][OTf]3, 4', are described. Both complexes were produced in high yield and fully characterized using NMR, IR, and UV-vis spectroscopies as well as elemental analysis and single-crystal X-ray crystallography. The solubility of 3' in acetonitrile showed a 283% improvement over its neutral precursor, whereas the solubility of complex 4' was effectively unchanged. Cyclic voltammetry indicates an ∼0.1 V positive shift for all waves, with some changes in reversibility depending on the wave. Bulk electrochemical cycling demonstrates that both 3' and 4' can utilize the second more negative wave to a degree, whereas 4' ceases to have a reversible positive wave. Flow cell testing of 3' and 4' with Fc as the posolyte reveals little improvement to the cycling performance of 3' compared with its parent complex, whereas 4' exhibits reductions in capacity decay when cycling either negative wave. Postcycling CVs indicate that crossover is the likely source of capacity loss in complexes 3, 3', and 4' because there is little change in the CV trace. Density functional theory calculations indicate that the ammonium group lowers the HOMO energy in 3' and 4', which may impart stability to cycling negative waves while making positive waves less accessible. Overall, the incorporation of a positively charged species can improve solubility, stored electron density, and capacity decay depending on the complex, features critical to high energy density redox flow battery performance.

Thin Bi1-xSbx wires with stibium concentration of 6 and 8at% in the free state and under elastic stretches are studied. Under 6-8% stretches the electron topological transition semiconductor-semimetal is found. The power factor is calculated.

Understanding the structural changes taking place during the assembly of single atoms leading to the formation of atomic clusters and bulk materials remains challenging. The isolation and theoretical characterization of medium-sized clusters can shed light on the processes that occur during the transition to a solid-state structure. In this work, we synthesize and isolate a continuous 24-atom cluster Ge244-, which is characterized by X-ray diffraction analysis and Energy-dispersive X-ray spectroscopy, showing an elongated structural characteristic. Theoretical analysis reveals that electron delocalization plays a vital role in the formation and stabilization of the prolate cluster. In contrast with carbon atoms, 4 s orbitals of Ge-atoms do not easily hybridize with 4p orbitals and s-type lone-pairs can be localized with high occupancy. Thus, there are not enough electrons to form a stable symmetrical fullerene-like structure such as C24 fullerene. Three aromatic units with two [Ge9] and one [Ge6] species, connected by classical 2c-2e Ge-Ge σ-bonds, are aligned together forming three independent shielding cones and eventually causing a collapse of the global symmetry of the Ge244- cluster.

Heterometallic clusters have attracted broad interests in the synthetic chemistry due to their various coordination modes and potential applications in heterogeneous catalysis. Here we report the synthesis, experimental, and theoretical characterizations of four ternary clusters ([M2(CO)6Sn2Sb5]3- (M = Cr, Mo), and [(MSn2Sb5)2]4-, (M = Cu, Ag)) in the process of capturing the hypho- [Sn2Sb5]3- in ethylenediamine (en) solution. We show that the coordination of the binary anion to transition-metal ions or fragments provides additional stabilization due to the formation of locally σ-aromatic units, producing a spherical aromatic shielding region in the cages. While in the case of [Mo2(CO)6Sn2Sb5]3- stabilization arises from locally σ-aromatic three-centre and five-centre two-electron bonds, aromatic islands in [(AgSn2Sb5)2]4- and [(CuSn2Sb5)2]4- render them globally antiaromatic. This work describes the coordination chemistry of the versatile building block [Sn2Sb5]3-, thus providing conceptual advances in the field of metal-metal bonding in clusters.

The article presents an analysis of the role of information and methodological support for the process of valuation of real estate objects in the general research procedure. In the context of modern regulation of valuation activities in the Russian Federation, the structure and content of general and special federal valuation standards are disclosed, as well as the main problems that have a negative impact on the scope and content of the study aimed at determining the value of assets. It is noted that the issues of the validity of the applied approaches and methods of real estate valuation are closely interconnected with the level of credibility, reliability and sufficiency of external, internal, analytical and regulatory information, on the basis of which various stages of calculating the value of objects are carried out. The proposed solution to the problems of information and methodological support for evaluation studies is aimed at increasing the level of reliability and validity of the final cost of objects. The authors propose a system of price-forming factors and indicators, the consideration of which, when implementing various assessment methods, is necessary in the context of the transformation of the national and regional economy.

Development of new antibacterial materials for solving biomedical problems is an extremely important and very urgent task. This review aims to summarize recent articles (from the last five and mostly the last three years) on the nanoparticle/polymer composites for biomedical applications. Articles on polymeric nanoparticles (NPs) and hydrogel-based systems were not reviewed, since we focused our attention mostly on the composites of polymeric matrix with at least one inorganic filler in the form of NPs. The fields of application of newly developed antibacterial NPs/polymer composites are described, along with their composition and synthetic approaches that allow researchers to succeed in preparing effective composite materials for medical and healthcare purposes. [ABSTRACT FROM AUTHOR]