Heavy-element-containing compounds and materials are among the most challenging objects for ab initio electronic structure modeling due to the interference of strong relativistic effects, typically multi-configuration nature of electronic states, and high density of levels in their spectra. A thorough modeling of these objects aimed at reliable predictions of their structure and optical,...
Currently, it is of interest to study the magnetic properties of HTSC at the mesoscopic level. One of the best methods of numerical modeling in such cases is the Monte Carlo method. In our work, an attempt is made to apply this algorithm to some unconventional superconductors. Calculations were based on Lawrence-Doniach model, Gibbs free energy was minimized using stochastic method. The survey...
Amorphous and microcrystalline silicon is important in electronics, energy and medicine due to its useful properties. Precisely, microcrystalline silicon is preferred for its high resistivity to degradation, electrical properties and special light absorption. However, producing high quality microcrystalline silicon is challenging. It requires precise control of process of crystallization and...
This work is devoted to the modelling of radiation effects of swift heavy ions in AlN. This material was chosen because it is promising for using in nuclear reactors. The multiscale model was employed. To describe the ions impact and further electron kinetics we use the TREKIS model based on MC-methods. After this, on atomic dynamic stage, MD-methods were applied to trace the atoms movement....
Ceramics based on mineral-like structures (garnets, scheelites, monazites) are being studied as promising matrices for the immobilization of radioactive waste. This paper presents an investigation of polycrystalline ceramic samples of Y2.5Nd0.5Al5O12 (YAG:Nd) obtained by spark plasma sintering. During the operation of such materials, the matrix structure undergoes intense radiation impact...
Copper (II) oxide (CuO) is a sustainable, stable, non-toxic photovoltaic material that can be produced using low-cost techniques. The primary objective of this research is to develop a heterostructure based on elongated CuO nanostructures with an inverted and branched architecture. In this heterostructure, the CuO layer serves as both, the support and the absorbing material for solar...
There are a lot of studies aimed at replacing lithium-ion batteries (LIB) with sodium-ion batteries (SIB) [1]. Potassium-ion batteries (PIB) are also promising electrochemical devices due to the potassium availability compared to lithium [3]. Unlike sodium, PIBs can use graphite as anode material, suggesting that the well-developed LIB system can be better transferred to the PIB system....
The selection of synthesis methods significantly influences the properties of nanomaterials intended for use in solid-state lighting device applications. In our study, Zinc borate nanophosphors doped with 1 mol% europium (Zn4B6O13:Eu3+) were synthesized using various methods such as the sol-gel, combustion, and solid-state reaction methods. The impact of the various method on the structural...
The investigation of nanoscale diamond-like carbon (DLC) coatings on acrylonitrile butadiene styrene plastic (ABS) substrates revealed a linear I-V characteristic, a decrease of resistivity from 12 ฮผOmโm to 3 ฮผOmโm, and of wetting angle from 52ยฐ to 38ยฐ with increasing thickness from 54 nm to 71 nm. The relative dielectric permittivity of the DLC coatings varies from 5.6 to 6.5, and at...
The crystal and thermodynamic properties of Tb2Ni2X (X = Al, Ga) are reported through measurements of X-ray diffraction (XRD), magnetic susceptibility, ฯ(T ), magnetization, M(ฮผ0H) and heat capacity, Cp(T ). XRD pattern analysis confirms the orthorhombic W2CoB2-type with the space group of Immm. ฯ(T ) at high temperature for both compounds follows the CurieโWeiss relationship giving an...
This work is devoted to the study of ion exchange resins Dowex 50WX8 200-400 mesh and Dowex 1X8 100-200 mesh, washed in solutions of iron salts, by nuclear gamma resonance. Unlike crystalline solids, ion exchange resins do not possess long-range order and cannot be described using the phonon concept.Traditionally, the nuclear gamma resonance method is used to study solids. Gel is a...
The variety of practical applications of materials with f and heavy d elements in the composition requires the development of theoretical methods for their correct interpretation and description. However, when studying optical properties, such as excitation energies, in materials containing lanthanides and actinides, it is almost impossible to achieve reliable, highly accurate results....
Monomolecular films formed on the surface of a liquid by self-organization of amphiphilic molecules are commonly called Langmuir monolayers. The arachidic acid Langmuir monolayers formed on a solution of cerium nitrate were studied in this work. We have identified unusual mode of the structural ordering of such monolayers. The results are based on the analysis of data obtained using the...
Ibuprofen is a representative of the group of non-steroidal anti-inflammatory drugs widely used in modern medical therapy. The drug formulations of Ibuprofen most often contain a racemic mixture of the two enantiomers with the S enantiomer being biologically active and the R being inactive. Cyclic dimers of Ibuprofen can be distinguished in condensed state of this compound that is confirmed by...
Spinel-type crystals $\mathrm{AMe_2O_4}$ encompass a wide range of practical applications like photocatalysis or spintronics, but often demonstrate non-trivial electronic and magnetic properties which theoretical description is mitigated. In this work, we performed DFT+U calculations for the most extensive set of neutral point defects in $\mathrm{Fe_3O_4}$ (magnetite) and $\mathrm{FeCr_2O_4}$...
Nickel ferrite spinel $\text{Ni}\text{Fe}_{2}\text{O}_{4}$ promising material in spin-based devices and non-volatile resistive memory. In this work we consider electronic structure of pristine and defective nickel ferrite. The orbital ordering, band gap and charge transfer are studied in the framework of density functional theory with account of strong electronic correlations (DFT+U method)....
Silicon (Si) has been considered as one of the most promising materials for photoelectrochemical (PEC) devices due to its low cost, established manufacturing process, and high theoretical photovoltage and saturation current density. However, developing Si-based PEC devices has been challenging, primarily because of silicon highly susceptibility to (photo)corrosion under PEC conditions. To...
In this study, the effect of proton irradiation on the structure and properties of Al2O3 โ YSZ ceramics based on ฮณ+ฮธ-Al2O3 + n% YSZ (n = 0, 1, 5, 10, 15 wt.%) nanopowders was analyzed. The phase composition of the powders, the structure, physical and mechanical properties of the Al2O3 - YSZ ceramics were studied taking into account the YSZ concentration and the pressing pressure. We have found...
This work is devoted to describing the design and parameters of a resonator for the future gradient spin flipper of a pulsed UCN source. Since this device must be installed strictly inside the warm zone of the superconducting magnet of the flipper, two geometric restrictions are imposed on it: a limitation on the outer radius, due to the heat-insulating casing of the superconducting magnet ,...
In the last few decades, low-dimensional magnetic materials have attracted considerable attention in experimental and theoretical studies. They have been found to exhibit physical phenomena such as ferroelectricity, spin liquid, spin ice, and properties inherent to multiferroics. This makes them promising for practical applications in spintronics and quantum computing. Such compounds include...
Ferrite oxide compounds of MFe2O4 (M = Co, Cu, Mn, Ni, Zn) with spinel-type crystal structures are being actively researched due to their attraction from both basic and practical viewpoints. These materials, both in bulk and nanosize, have drawn significant interest due to their unique magnetic properties, such as various magnetic phase transitions, topological destruction effects,...
Undoped ZnAl2O4/ZnO mixed phases (hereafter called ZZ) and Sm3+ doped ZZ nanopowders were synthesized by precipitation method and annealed at 750 โ for 3.5 h. This study aimed to investigate the effect of varying the Sm3+ concentration on the ZZ mixed phases nanopowders. The effect of Sm3+ on the structure, morphology, optical and luminescence properties were studied in detail. The X-ray...
Hafnium oxide HfOx is one of the promising materials in modern electrical physics. Due to its high dielectric constant, chemical and physical stability, its thin films are often used in the manufacture of capacitors, transistors and other microelectronic devices, such as gas detectors. In addition, hafnium oxide has a resistive switching effect. This effect is the basis for creating unique...
The main idea of the UCN source at a periodic pulsed reactor is effective pulsed accumulation of the UCN trap [1].The amount of neutron density accumulated in the trap depends on many factors: neutron bunch duration at the trap entrance, the effectiveness of transportation, absorption by the walls of the UCN trap itself, etc. The forced distance of the UCN trap from the neutron birthplace...
