The structural and transport features of the behavior of the fluorine ion sublattice of Pb0.78Sr0.19K0.03F1.97 solid solution have been studied by the ab initio molecular dynamics method. It is shown that the local diffusion of fluorine anions changes with the nature of dopant atom, which is consistent with the experimental transport characteristics.

The structural and ionic transport properties of the low‐index undoped ZrO2/CeO2 interfaces are simulated within the framework of density functional theory (DFT). These results show partial “melting” of the oxygen subsystem with significant disordering of the oxygen layers located between the layers of zirconium and cerium atoms. This leads to the existence of anomalously high ionic diffusion in simple undoped oxide phases with the fluorite structure.

Based on the analysis of publication activity, trends in the development of the main sections of solid state ionics have been formulated by using expertly curated abstract & citation database of peer-reviewed scientific literature Scopus. Promising areas of research related to in situ and operando experiments, artificial intelligence (machine learning), and the design of new devices using superionic materials are indicated.

A three-layer Zr0.8Sc0.2O1.9/Ce0.9Gd0.1O1.95/Pr2CuO4 heterosystem has been studied by the molecular dynamics method in a computational cell ∼110 × 110 × 470 Å3 in size. It is shown that the main crystallographic characteristics are retained for all layers. It follows from the analysis of pair correlation functions that all oxide phases in the heterosystem exhibit oxygen sublattice disorder, which is especially pronounced in zirconium and cerium oxides. The calculated values of layer-by-layer oxygen diffusion coefficients, as well as the diffusion activation energies, are compared with the data of both direct physical and computer experiments. Individual paths of oxygen anion jumps through the Zr0.8Sc0.2O1.9/Ce0.9Gd0.1O1.95 and Ce0.9Gd0.1O1.95/Pr2CuO4 interfaces are traced.

The oxygen diffusion has been simulated by the molecular dynamics method in the solid solutions of PrBaCo 2 O 5.5 -based double perovskites: PrBa 0.5 Sr 0.5 Co 2 O 5.5 with random substitution of half of Ba atoms by Sr atoms, PrBa 0.5 Sr 0.5 CoFeO 5.5 with random substitution Ba → Sr and Co → Fe, PrBa 0.5 Sr 0.5 CoCuO 5.5 with random substitution Ba → Sr and Co → Cu, and PrBa 0.5 Sr 0.5 CuFeO 5.5 with random substitution Ba → Sr and random substitution of Co atoms by Fe and Cu atoms. It is shown that, varying the oxygen nonstoichiometry and/or chemical composition of solid solutions based on PrBa 0.5 Sr 0.5 Co 2 O 5.5 , one can significantly change the coefficient of thermal expansion of the materials. It is established for the first time that the maximum difference between the mobilities of oxygen atoms of different types observed in PrBa 0.5 Sr 0.5 Co 2 O 5.5 significantly decreases at partial substitutions of cobalt by iron and copper. In the PrBa 0.5 Sr 0.5 CuFeO 5.5 solid solution, the oxygen atom mobility in the (Cu,Fe)–O layers becomes somewhat higher than that in the Pr–O layers.

The specific features of the fluorine-ion transport in nanostructured samples of Рb1 – xCdxF2 solid solutions are studied by the molecular dynamics method. The diffusion coefficients DF of fluorine ions in these samples increase by several orders of magnitude (at room temperature) as compared to bulk crystals. The experimentally observed maximum of fluorine diffusion at 30 mol % CdF2 could be reproduced for spherical nanoparticles more than 15 nm in size. It is shown that the mobility of the F– ions located on the surface of nanospherical particles exceeds several times the mobility of fluorine anions in the particle bulk.

A two-layer Zr0.8Sc0.2O1.9/Ce0.9Gd0.1O1.95 heterostructure has been modeled by the molecular dynamics method in a box containing about 27 thousand atoms. It is shown that this system retains on the whole the crystallographic characteristics of layers doped with zirconia and ceria, having a fluorite structure. Crystal structure distortions are observed in a narrow boundary layer with a thickness of few angstrom. An analysis of pair correlation functions indicates that the oxygen sublattice in the heterostructure is disordered. The calculated values of the layer-by-layer diffusion coefficient of oxygen and the diffusion activation energy are compared with the data of both direct physical and computer experiments.

The possibilities of describing correctly interfaces of different types in solids within a computer experiment using molecular statics simulation, molecular dynamics simulation, and quantum chemical calculations are discussed. Heterophase boundaries of various types, including grain boundaries and solid electrolyte‒solid electrolyte and ionic conductor‒electrode material interfaces, are considered. Specific microstructural features and mechanisms of the ion transport in real heterophase structures (cationic conductor‒metal anode and anionic conductor‒cathode) existing in solid state ionics devices (such as solid-state batteries and fuel cells) are discussed.

Molecular dynamics simulation has been used to develop a realistic atomistic model of two-layer Ce1 – xGd x O2 – δ|YSZ heterosystem. It is shown that Ce1 – xGd x O2 – δ and YSZ layers (about 15 and 16 Å thick, respectively) retain their crystal structure on the whole. The main structural distortions are found to occur near the Ce1 – xGd x O2 – δ|YSZ geometric interface, within a narrow interfacial region of few angstroms thick. Both the generalized diffusion characteristics of the system as a whole and the oxygen diffusion coefficients in the layers are calculated, and the diffusion activation energies are determined.

The recently introduced theory of general value addresses two distinct components of value: monetary and nonmonetary. The introduction of the nonmonetary component of value helps explain many types of decisions and choices, which were not clearly understood before, and helps with the strategic planning and actions. This paper introduces a methodology of measuring nonmonetary value of goods and services in the perception of people. The indifference point between two choices is used to measure the difference of nonmonetary components in terms of the difference of the monetary components with the opposite sign. This method was used to measure relative nonmonetary values (the difference of the monetary components) of various goods and services in the perception of different social groups. Keywords: value, nonmonetary, utility, preference, behavioral economics, decision-making, personal choice Classifications: A130, D01, D03

Electronic structure of (SiO2)3 clusters was calculated by the density functional method. Charge states were determined using various functionals, bond lengths and total energies of clusters were estimated.

The concept of value has been a central concern of economics since its inception as a discipline. The labor theory of value in classical economics was followed by the neoclassical perceptional theory of utility, and behavioral economics introduced a psychological track in it. The recently introduced theory of general value makes the next step by introducing two distinct components of value: monetary and nonmonetary. The introduction of the nonmonetary component of value helps explain many types of decisions and choices, which were not clearly understood before, and helps with the strategic planning and actions. This paper introduces a methodology of measuring nonmonetary value of jobs in the perception of people. The indifference point between two choices is used to measure the difference if nonmonetary components in terms of the difference of the monetary components with the opposite sign. This method was used to measure relative nonmonetary values (the difference of the monetary components) of various jobs in the perception of different social groups.

A molecular dynamics simulation of solid tin(II) fluoride nanostructures formed in internal channels of single-walled carbon nanotubes (SWCNTs) has been performed using two types of model potentials—without and with inclusion of the polarization of ions. For the potential taking into account the polarization of ions, an ordered SnF 2 @SWCNT structure is reproduced: in SWCNT(10, 10), it has the form of the SnF 2 internal nanotube. At the same time, the SnF 2 @SWCNT(11,11) structure is substantially disordered (glass-like). It has been found that heating of the SnF 2 @SWCNT model system produces a superionic state characterized by a high mobility of fluorine ions without migration of tin ions. The model potentials disregard the covalent character of Sn-F bonds and the specific interactions of a lone electron pair of the Sn 2+ ion. This makes it impossible to completely reproduce the properties of SnF 2 at normal pressures. However, some characteristics of the SnF 2 high-pressure modification can be reproduced if the polarization of ions is taken into account.

Oxygen diffusion in the new class of cuprates Pr 2- x Sr x CuO 4-δ ( x = 1) with perovskite structure has been simulated in the temperature range of 300–2100 K for the first time. A calculation has shown the presence of anisotropy of oxygen motion: the oxygen transport in PrSrCuO 3.7 in the temperature range of 300–2100 K is mainly two-dimensional, with an activation energy of no more than 0.40 eV. The coefficient of thermal expansion of PrSrCuO 3.7 (9.9 × 10 −6 K −1 in the range 1300–2100 K) and the oxygen diffusivity in it, which exceed the corresponding values for La 2- x Sr x CuO 4-δ , indicate that this compound is promising as an electrode material with a mixed ionic-electronic conductivity for various electrochemical devices. The results expand the previous concepts of the oxygen-ion transport in complex cuprates.

Morphologies of AgI1-xBrx (0 <= x <= 1) nanocrystalline structures formed in carbon single-wall nanotubes (SWNT), of diameter d = 11.5-17.6 angstrom, have been investigated by molecular dynamics simulation. For AgI1-xBrx in a (10, 10) carbon SWNT (d = 13.54 angstrom), ionic motion characteristics at different temperatures have been studied. Calculations confirm the experimentally based suggestion that structural differences between AgI and AgBr in carbon SVVNTs are less pronounced than in the bulk crystals. According to the simulation results, in tubes taken out from the melt, AgBr and AgI1-xBrx tend to form hexagonal nanotubes after annealing, similar to those formed by AgI. A superionic state, with significant silver ion mobility against a stable anion sublattice, can be observed in the simulated AgI1-xBrx@SWNT; the superionic conduction temperature range shifts downward with increasing bromine content. At temperatures below and just above the nanocrystal melting point, ion migration is faster in more bromine-rich AgI1-xBrx@ SWNT systems, while at T >= 1000 K, the composition dependence of ion diffusion coefficients is much less pronounced. Just as in AgI@SWNT systems, the ion transport characteristics change significantly with a transition from single-wall AgI1-xBrx nanotubes in carbon SWNTs to structures with extra ions in the tube center.

The structural and transport properties of the layered cuprate Pr 2 CuO 4 have been studied in the temperature range 300–2100 K using molecular dynamics simulation. The first evidence is presented for a premelting effect in Pr 2 CuO 4 : disordering on one of its oxygen sites and abnormally fast oxygen diffusion at temperatures above 1700 K. We have clarified the microscopic mechanism of oxygen ion transport in this material. The large oxygen diffusion coefficient ( D > 10 −7 cm 2 /s) obtained in our simulations of the layered cuprate Pr 2 CuO 4 suggests that it has considerable potential as a host for electrode materials with mixed ionic-electronic conductivity.

Oxygen diffusion in layered cuprate La2SrCu2O6 has been simulated by the molecular dynamics method in the temperature range of 300–2500 K. The lattice is found to transform at temperatures above 1550 K; this transformation is accompanied by a change in the pair correlation functions. The abrupt change in the oxygen diffusion coefficient in the range of 1500–1550 K may indicate the presence of a phase transition to the superionic state. The motion of oxygen anions could be traced at the microscopic level. It has been proven for the first time that the La2SrCu2O6 crystal lattice allows, along with displacements of O1 ions within the CuO2 layer, their migration from the crystallographic positions to the intermediate unoccupied O3 positions. The motion of O2 anions is also fairly complicated: they move not only in their layer over the O2 positions but they also jump to the neighboring layer to occupy the O1 positions. The oxygen diffusion coefficient in layered cuprate La2SrCu2O6 exceeds that in cuprates with perovskite structure and structure of the K2NiF4 type (at the same temperatures), which indicates that this material has good prospects for electrodes with mixed ionic-electronic conductivity.

Filling of carbon single-wall nanotubes (SWNTs), of diameter d=11.5–15Å, by silver iodide from the melt is modeled by molecular dynamics. Formation of AgI inorganic nanotube (INT) structures in the SWNTs on cooling, and ion diffusion in AgI within the tubes (AgI@SWNT) at 500–1200K are studied. Dependence of AgI@SWNT structure on carbon SWNT geometry is examined. For d≤14.2Å, a single-wall AgI INT is formed within the carbon tube, with structure (geometry) depending on d; in wider tubes, there are extra silver and iodine ions in the central region. The calculated diffusion coefficients of silver and iodine ions and their diffusion activation energies depend on the nanotube geometry. Ion mobilities within carbon SWNTs are significantly lower, and diffusion activation energies, higher than in the bulk phase of AgI, especially in narrow tubes. In the (11,11) carbon SWNT, the widest among those simulated, the activation energy for silver ion diffusion becomes close to the “bulk” value, while for iodine ions, larger in size, the difference remains.

The time-shift asymmetric correlation analysis method is introduced for stock exchanges with different but non-overlapping trading hours to analyze the degree of global integration between stock markets of different countries and their influence on each other. Next-day correlation (NDC) and same-day correlation (SDC) coefficients are introduced. Correlations between major U.S. and Asia-Pacific stock market indices are analyzed. Most NDCs are statistically significant while most SDCs are insignificant. NDCs grow over time and the U.S. stock market plays a pacemaking role for the Asia-Pacific region. The correlation coefficients can be used as a measure of the degree of globalization for the corresponding countries.

The specific features of the regeneration growth of colored varieties of beryl (emerald and bixbite) grown under hydrothermal conditions are studied. Habits and crystallographic features of the faceting of crystals grown on seeds of different orientations are analyzed. Micromorphology of the growth surfaces of emerald and bixbite single crystals is examined using optical and atomic force microscopy. Fractal dimensions of the regeneration surfaces were evaluated for beryl single crystals.