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Volume 70, Nº 6 (2025)
ДИФРАКЦИЯ И РАССЕЯНИЕ ИОНИЗИРУЮЩИХ ИЗЛУЧЕНИЙ
ACCURATE MEASUREMENT OF THE ROCKING CURVE OF A PLANAR COMPOUND REFRACTIVE LENS FOR SYNCHROTRON RADIATION FOCUSING
Resumo
We present the results of the first measurement of the rocking curve of a nanofocusing compound refractive lens made of silicon, used for focusing synchrotron radiation (SR) at the "KISI-Kurchatov" source. The obtained curve is accurately approximated by a Gaussian function, and its width agrees with a previously developed analytical theory describing SR propagation in multi-element focusing systems. The results demonstrate the feasibility of using the rocking curve as an alignment characteristic of the experimental setup when working with silicon lenses at second-generation SR sources.
Crystallography. 2025;70(6):899-904
899-904
X-RAY DIAGNOSTICS OF MULTILAYER Ti/Ni MIRRORS WITH VARIOUS CONFIGURATIONS OF Si BUFFER INSERTS USING X-RAY REFLECTOMETRY AND STANDING X-RAY WAVES METHODS
Resumo
This article investigates the periodic structure of Ni/Ti X-ray mirrors with different configurations of Si buffer layers using X-ray reflectometry and standing X-ray wave techniques. Depth profiles of electron density and the distributions of Ni and Ti elements within the films were obtained. Films with period structures of Ti/Ni, Ti/Si/Ni, Ti/Ni/Si, and Ti/Si/Ni/Si were examined. The results show that the structure featuring a Si buffer layer inserted both between layers within a period and between the periods themselves (Ti/Si/Ni/Si) is optimal as a mirror configuration in terms of reflectometry intensity.
Crystallography. 2025;70(6):905-911
905-911
PROBLEMS WITH SYNCHROTRON RADIATION PHASE CONTRAST IMAGING OF MICRO-OBJECTS IN CRYSTALS
Resumo
Problems in experimental study of real crystal structures using phase-contrast imaging with synchrotron radiation (SR) are discussed and methods for their solution are proposed. The experiment was conducted at the Pohang Light Source, in Pohang City, Republic of Korea. A diamond crystal was examined. The capabilities of the method in studying weak changes in crystal density under conditions of spatially non-uniform beam intensity, beam statistical noise and detector imperfections are analyzed. Images of various shapes and sizes were obtained, showing the presence of defects. However, a more detailed analysis is required to identify the defects.
Crystallography. 2025;70(6):912-916
912-916
EFFECT OF SOLVENT ISOTOPE COMPOSITION (H2O AND D2O) ON LYSOZYME OLIGOMER FORMATION UNDER CRYSTALLIZATION CONDITIONS
Resumo
Using the method of small-angle X-ray scattering (SAXS), the temperature dependencies (in the range of 4 to 30°C with a 1°C step) of the structure of a lysozyme solution during the growth of tetragonal crystals were obtained for H2O and D2O solvents. It was found that, regardless of the solvent type, dimers and octamers form in the lysozyme crystallization solution. The volume fractions of the oligomers (dimers and octamers) are inversely proportional to the temperature change, both in the case of the H2O solvent and the D2O solvent. Under identical temperature conditions, the volume fraction of oligomers in the lysozyme crystallization solution in D2O is approximately 8% higher than in H2O. However, the same oligomer content in the lysozyme crystallization solutions in H2O and D2O is achieved when the temperature of the H2O solution is approximately 10°C lower than that of the D2O solution. This may be explained by the distinct influence of the solvent on protein hydration.
Crystallography. 2025;70(6):917-924
917-924
КРИСТАЛЛОХИМИЯ
RELATIONSHIP BETWEEN LATTICE PARAMETERS AND CATION RADIUS IN THE HOMOLOGOUS SERIES OF RARE-EARTH OXOFLUORIDES WITH FLUORITE STRUCTURE
Resumo
The relationship between the lattice parameters and the ionic radii rR of cations in the homologous series of rare earth oxofluorides with the general formula ROF (12R = La–Er, Y) and the fluorite structure (sp. gr. Fm3m) was investigated. It was found that for all ROF compounds the equation (Å) is satisfied: a = 2.365rR + 3.004. The special electronic structure of the Y3+ cation does not lead to deviation from the correlation equation. The obtained equation makes it possible to determine from the structural data for fluorite oxofluorides AnOF (An = Ac, Pu, Cm, Cf) unknown ionic radii of triply charged actinium cations Ac3+ (rAc = 1.24 Å) and actinides Pu3+ (rPu = 1.14 Å), Cm3+ (rCm = 1.10 Å), Cf3+ (rCf = 1.08 Å) for the coordination number 8. Within the framework of the crystallochemical model, the values of the "effective" radii of the fluorine ion (rF = 1.249 ± 0.017), oxygen ion (rO = 1.373 ± 0.005) and the average radius of the anion (rO,F = 1.327 ± 0.009 Å) for fluoride, oxide and oxofluoride compounds with the fluorite structure were refined. The values of rF, rO and rO,F can be used in calculations of the crystallochemical properties of fluorite oxofluoride solid solutions.
Crystallography. 2025;70(6):925-930
925-930
SIMULATION OF HUANZALAITE MgWO4 BY THE METHOD OF INTERATOMIC POTENTIALS
Resumo
The structure and properties of huanzalaite MgWO4 has been investigated by computer simulation study based on the method of empirical interatomic potentials. The results of simulation of structural, elastic and thermodynamic properties of MgWO4 and their comparison with available experimental data and ab initio calculations are presented.
Crystallography. 2025;70(6):931-935
931-935
SIMULATION OF ZnWO4–MgWO4 SOLID SOLUTIONS BY THE METHOD OF INTERATOMIC POTENTIALS
Resumo
The simulation of Zn1-x
MgxWO4 solid solutions is accomplished using the method of empirical interatomic potentials. The dependences of the structure, elastic, and thermodynamic properties on the composition have been established. It is shown that as the fraction of magnesium in a solid solution increases, the volume, density, enthalpy, heat capacity, and entropy decrease, and the shear and bulk moduli increase. The dependencies are close to linear. The mixing functions are calculated. The enthalpy and volume of mixing are different from zero, which indicates that the solution is not ideal. It is shown that the Zn1-x
MgxWO4 solution exists in the entire range of compositions.
Crystallography. 2025;70(6):936-941
936-941
REAL STRUCTURE OF CRYSTALS
MICROSTRUCTURE OF TWO-PHASE NbS3 WHISKERS
Resumo
The structure of two-phase whiskers of niobium trisulfides NbS3 was studied using various electron microscopy methods. The whisker is a highly textured polycrystal consisting of two crystalline phases NbS3-I and NbS3-II. Two orientation relationships between the phases were determined using electron diffraction. Pores and dislocations were found at the interphase boundaries, and models of the interphase boundaries were proposed. The structure of stacking faults of various types in the crystalline phase NbS3-II was revealed.
Crystallography. 2025;70(6):942-950
942-950
СТРУКТУРА НЕОРГАНИЧЕСКИХ СОЕДИНЕНИЙ
Evolution of the Cluster Structure of Fluorite Nonstoichiometric Crystals of the Homological Series Ca1–xRxF2+x (R = Sc, Y, La–Lu) in the Composition–Temperature System
Resumo
The unified model of the cluster structure of fluorite nanostructured crystals proposed by the authors in the temperature–composition (T–x) system was used to clarify the evolution of the cluster structure of the crystals of the homologous series Ca1–xRxF2+x (R = La–Lu, Y). Defective structures of Ca0.75Nd0.25F2.25, Ca0.80Tb0.20F2.20 and Ca0.75Y0.25F2.25 were studied by X-ray diffraction analysis at 293 and 85 K. They are based on octa-cubic clusters with cuboctahedron cores (F12). The nuclei are formed by interstitial anions at position 32f (f-type clusters in Ca0.75Nd0.25F2.25 and Ca0.80Tb0.20F2.20) and position 48i (i-type clusters in Ca0.75Y0.25F2.25). Obtaining diffraction data with a resolution of 0.29 Å made it possible to identify cation displacements at positions 24e and 32f in Ca0.75Y0.25F2.25 and clarify the occupancies of these positions. Lowering the temperature from 293 to 85 K does not change the cluster structure of Ca0.75Nd0.25F2.25, Ca0.80Tb0.20F2.20 and Ca0.75Y0.25F2.25. An electron diffraction study of the Ca0.75Nd0.25F2.25 crystal revealed, for the first time, diffuse scattering from structural defects with dimensions on the order of one unit cell in crystals of the Ca1–xRxF2+x homologous series.
Crystallography. 2025;70(6):951-962
951-962
NEW DATA ABOUT ISOMORPHISM IN THE EUDIALYTE GROUP MINERALS. XIII. CRYSTAL STRUCTURE OF "FERROFEKLICHEVITE" – POTENTIALLY NEW HIGH CALCIUM MINERAL FROM KHIBINY MASSIF
Resumo
The crystal structure of a high-calcium eudialyte group mineral from alkaline rocks of the Khibiny massif has been studied. Trigonal cell parameters: a = 14.221(1), c = 30.04(1) Å, V = 5261.3(4) Å3, space group R3m. The structure has been refined to a final divergence factor of R = 2.8% in the isotropic approximation of atomic displacements using 1714 reflections with F > 3σ(F). The studied mineral is similar in chemical composition to feklichevite, from which it differs in the dominance of divalent iron, as well as a lower calcium content and a higher manganese content. The structural features of representatives of the eudialyte group with an increased calcium content from three alkaline massifs are discussed.
Crystallography. 2025;70(6):963-968
963-968
STRUCTURE OF MACROMOLECULAR COMPOUNDS
STRUCTURAL STUDIES OF THE DYNAMICS OF BINDING OF MIF TO PHENYLISOTHIOCYANATE
Resumo
The intermediate states of the macrophage migration inhibition factor (MIF) complex with phenylisothiocyanate (PITC), a covalent inhibitor of the protein under study, were studied by X-ray diffraction analysis. It has been shown that prior to covalent modification of the N-terminal proline, non-covalent binding of the inhibitor occurs at the retention site, which was discovered for the first time. The retention site was identified by using the technique of short-term infusion of a MIF crystal in a cryosolution containing a ligand, followed by instant freezing in a nitrogen jet to collect diffraction data at 100 K. A comparison of the structure with the structure obtained using the crystallization of a pre-modified protein revealed details of the dynamics of PITC binding.
Crystallography. 2025;70(6):969-975
969-975
КРИСТАЛЛОГРАФИЯ В БИОЛОГИИ И МЕДИЦИНЕ
CALCULATION OF THE STABILITY OF CANDIDATE VACCINES FOR THE PREVENTION OF DENGUE FEVER AND THEIR COMPLEXES WITH TOLL-LIKE RECEPTORS USING MOLECULAR DYNAMICS
Resumo
Rational vaccine design requires not only the prediction of immunogenic epitopes, but also a careful assessment of the structural stability of candidates and their ability to effectively interact with innate immunity receptors. The stability of four candidate vaccines and their complexes with toll-like receptors was assessed using molecular dynamics modeling using the Gromacs-2023 software package. The structures of the complexes of the considered chimeric candidate proteins for the Dengue virus vaccine with extracellular domains (ectodomains) of human toll-like receptors TLR4 and TLR8 were obtained as a result of molecular docking performed by the ZDOCK server. The affinity of the complexes was evaluated using the PRODIGY server.
Crystallography. 2025;70(6):976-983
976-983
ФИЗИЧЕСКИЕ СВОЙСТВА КРИСТАЛЛОВ
984-990
Anisotropy of Mechanical Properties of CdTe-Based Crystals
Resumo
Samples of CdTe-based crystals were characterized. Elemental and phase composition of samples were determined. Microhardness of samples was studied on two perpendicular surfaces. It is shown that in crystals with main CdTe phase and varied dopants the mechanical anisotropy is not observed. In crystals with main CdZnTe the anisotropy of microhardness is observed, it is connected with different lengths of Cd–Te and Zn–Te bonds, which results in nonsymmetrical distortions of crystal lattice. Difference in microhardness of CdTe crystals observed in work is explained by difference of structural parameters.
Crystallography. 2025;70(6):991-997
991-997
EFFECT OF DEFORMATIONS ON PHOTOLUMINESCENT AND PIEZO CATALYTIC PROPERTIES OF ZnO TETRAPODS
Resumo
The interrelation of photoluminescent and piezocatalytic properties of ZnO is studied using the example of an array of tetrapods subjected to mechanical stretching and an array of tetrapods in an organic contaminant solution during ultrasonic treatment. The effect of tensile stresses on luminescent properties is demonstrated: with a 4% elongation, the integral intensity of the ultraviolet photoluminescence band in ZnO tetrapods decreases by 25%, and its maximum is mixed by 1.27 nm in the long-wavelength region. It has been shown that with ultrasound assistance with a frequency of 40 kHz and a power of 120 W, the efficiency of catalysis using ZnO tetrapods increases by 42%. The reason for the observed effects is the mechanically enhanced charge separation by piezoelectric fields. The mechanism of acceleration of catalysis under ultrasonic action is discussed.
Crystallography. 2025;70(6):998-1002
998-1002
COMPUTER SIMULATION OF FLUORINE MOBILITY IN SOLID SOLUTIONS WITH FLUORITE STRUCTURE Pb0.8M0.2F2 AND Pb0.75M0.2K0.05F1.95 (M = Ca, Ba)
Resumo
The classical molecular dynamics was used to calculate the fluorine ion mobility in Pb0.8M0.2F2 and Pb0.75M0.2K0.05F1.95 (M = Ca, Ba) solid solutions with fluorite structure under normal conditions. It was shown that isovalent substitution of lead atoms by calcium atoms in a lead fluoride crystal increases the mobility of fluorine ions, while a similar substitution by barium atoms decreases it. Heterovalent substitution of Pb → K naturally increases the fluorine ion mobility in Pb0.75Ca0.2K0.05F1,95 and Pb0.75Ba0,2K0.05F1,95 solid solutions.
Crystallography. 2025;70(6):1003-1008
1003-1008
ПОВЕРХНОСТЬ, ТОНКИЕ ПЛЕНКИ
ANNEALING-INDUCED STRUCTURAL TRANSFORMATION IN NiO THIN FILMS
Resumo
The analysis of the results of structural studies using X-ray and electron microscopic diagnostics of NiO films obtained by magnetron sputtering is carried out. The difference in the phase and structural composition of films of different thicknesses before and after annealing is shown. The reasons for these differences are discussed, as well as the role of the interface layer for obtaining stable nanoscale NiO films on sapphire substrates.
Crystallography. 2025;70(6):1009-1018
1009-1018
CRYSTAL GROWTH
DOPING ANTHRACENE CRYSTALS WITH ASSOCIATED IMPURITIES DURING THE GROWTH FROM SOLUTION
Resumo
The paper presents a study on the effect of aging of solutions on the growth features of anthracene crystals. It was found that prolonged storage (>3 weeks) of saturated solutions in air leads to their aging, accompanied by the precipitation of accompanying yellow needle-shaped crystals alongside the anthracene crystals. The structure of these accompanying needle-shaped crystals was determined by single-crystal X-ray diffraction in the space group P21/c (Z = 4) and was shown to consist of 9,10-anthraquinone molecules. The formation of solid solutions based on co-crystallization of anthracene and 9,10-anthraquinone molecules was not observed. It is shown that the observed long-wavelength shift in the fluorescence spectrum of crystals, which occurs when using certain commercial grades of anthracene for solution growth, is associated with the presence of a homologous impurity–tetracene–in the starting material. The crystallochemical aspects of the incorporation of concomitant impurity molecules into the crystal structure of anthracene are discussed.
Crystallography. 2025;70(6):1019-1032
1019-1032
PREPARATION, FEATURES AND SOME PROPERTIES OF CRYSTALLINE HYDRATES OF NICKEL CHLORIDE
Resumo
The temperature dependence of solubility in the NiCl2-H2O system in the temperature range of 25–60°C has been studied. The temperature ranges of crystallisation of NiCl2·6H2O and NiCl2·4H2O compounds have been determined. Single crystals of nickel chloride hexahydrate and tetrahydrate have been obtained, the size and quality of which have allowed the equilibrium faceting and optical spectra to be estimated. A comparative analysis of the thermal stability of the crystal hydrates obtained was carried out. It was found that the transparency band in the short wavelength range for nickel chloride crystals is shifted to the long wavelength range compared to the nickel sulphate crystal.
Crystallography. 2025;70(6):1033-1041
1033-1041
EFFECT OF HIGH TEMPERATURE ON PROTEINASE K CRYSTALLIZATION PREDICTED BY MOLECULAR DYNAMICS
Resumo
Molecular dynamics simulations revealed a notable thermal stability of the precursor cluster of proteinase K crystals (a dimer formed prior to crystallization) within the 20–60°C temperature range. This finding led to the hypothesis that crystallization at an atypically elevated temperature (50–60°C) could be feasible. This theoretical prediction was subsequently confirmed experimentally: proteinase K crystals were successfully grown after incubation at 60°C. The results not only demonstrate the predictive power of the molecular dynamics approach employed here for identifying optimal protein crystallization conditions, but also open new opportunities for capturing the catalytically relevant conformation of proteinase K.
Crystallography. 2025;70(6):1042-1047
1042-1047
THE EFFECT OF POSTGROWTH ANNEALING ON THE DISLOCATION STRUCTURE OF GERMANIUM CRYSTALS
Resumo
The effect of postgrowth annealing on the dislocation structure of germanium low-dislocation-density single crystals 100 mm in diameter grown by the Czochralski method has been studied. The annealing was performed at 700°C for 40 h in the thermal unit of crystal puller before cooling. It was found that the dislocation density ranging from 14 to 105 cm−2 in crystals growing with postgrowth annealing. The average dislocation density in crystals growing without annealing is on five times more.
Crystallography. 2025;70(6):1048-1052
1048-1052
SYNTHESIS OF CRYSTALS OF ULTIMATE SULFIDES IN SULFUR MELT IN A STATIONARY TEMPERATURE GRADIENT
Resumo
The possibilities of crystal growth of ultimate sulfides in molten sulfur in a stationary temperature gradient are described. The optimum synthesis mode is achieved when the temperature of the hot end (charge) is 550°C, the temperature of the cold end (crystallization) is 460°C. As a result, crystals of TiS3, ZrS3, HfS3, V40S60, NbS3, TaS3, PdS2, CuS, Ag2S, metallic Au, HgS, CdS, Ga2S3, In2S3, SiS2, SnS2, PbS, Sb2S3 and Bi2S3 of millimeter and submillimeter size were obtained. Only polycrystalline agglomerates of tens of microns in size were obtained when transferring some metals, such as tungsten. The possibility of obtaining crystals of double sulfides is shown using CrPS3 as an example. The considered technique allows obtaining crystals of the required quality without using special equipment. The small size of the crystals is sufficient for laboratory study.
Crystallography. 2025;70(6):1053-1059
1053-1059
ИСТОРИЯ КРИСТАЛЛОГРАФИИ
HOMOLOGOUS SERIES OF 15 RF3 (ZR=57La–71Lu) IN THE CATEGORICAL CRYSTALLOCHEMICAL TETRAHEDRON: "POLYMORPHISM – ISOMORPHISM – TRUE MORPHOTROPY – STRUCTURAL HOMOLOGY"
Resumo
The homologous series of 15 RF3 (R = 57La–71Lu) is based on the atomic number (Z) of the chemical elements ZR. It is a T–x–quasi–system (QS) "LaF3–LuF3" of 14 partial QS–N systems (N 1 to 14): 57LaF3–58CeF3, 58CeF3–59PrF3, and further to 70YbF3–71LuF3 (ΔZ = 1). The crystal–chemical category triad isomorphism, polymorphism, and morphotropy are the "homologous parameters" of the RF3 series. The series was first proposed as the vertex of the "structural homology" (SH) of the crystal–chemical tetrahedron. The SH vertex is associated with the vertices of isomorphism by five and polymorphism by nine QS–N. On the edge of "SH – true morphotropy" there are QS–8 (GdF3–TbF3 with peritectic) and QS–11 (HoF3–ErF3 with eutectic) phase reactions of absolute true morphotropic transformation.
Crystallography. 2025;70(6):1060-1070
1060-1070