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All-solid-state batteries are typically manufactured under high pressure to decrease the resistance of the solid interface. However, until now, there has been a lack of research concerning changes in the structure of solid electrolytes owing to pressurization. Our study addresses this gap by exploring the structural modifications of the sulfide solid electrolyte Li3PS4 under high-pressure conditions. We observed a tendency for PS4 molecules to converge upon each other in both β-Li3PS4 and g-Li3PS4 crystals when subjected to a pressure of 100 MPa. In g-Li3PS4, X-ray scattering and pair distribution function analyses following pressure application and subsequent return to ambient conditions remained consistent with pre-compression measurements. Conversely, in β-Li3PS4 crystals, post-pressure X-ray scattering differed from pre-compression measurements, suggesting pressure-induced atomic rearrangement within the crystal lattice. This underscores the importance of accounting for pressure-induced structural changes, especially in computational simulation studies where crystal structures are often assumed to remain static pre- and post-pressurization. Our findings demonstrate that under high pressure, the crystal structure of Li3PS4 slightly changes by approximately 1~2%, rendering it a viable candidate for utilization as a solid electrolyte in all-solid-state batteries. [ABSTRACT FROM AUTHOR]

The crystal structure of Michaelis complex of the bovine trypsin with N‐α‐benzoyl‐l‐arginine ethyl ester (BAEE) was determined at 2.30 Å resolution. The structure of enzyme‐substrate complex was solved in space group H32. The active site of trypsin was found to be occupied with the N‐α‐benzoyl‐l‐arginine ethyl ester. The hydrolyzed product of substrate molecules was also crystallized with trypsin. The substrate was embedded within the S1 binding site of the enzyme, and showed contacts with Gly‐195, Ser‐216, and Ser‐192. Some water molecules were also found within the vicinity of catalytic residues of enzyme. Interestingly, the hydrolyzed product present within the crystal lattice was found to be with inverted configuration. The crystal structure of trypsin in‐complex with N‐α‐benzoyl‐l‐arginine ethyl ester has never been reported previously. [ABSTRACT FROM AUTHOR]

In this study, the element substitution technique was utilized to create a solid solution, which in turn allowed for the manipulation of lattice parameters. The microwave dielectric properties of Mg 1.8 R 0.2 Al 4 Si 5 O 18 (R=Mg, Ni, Zn, Cu, Sr, Ca, Ba) ceramics were investigated following the substitution of Mg2+ ions. The influence of microstructural alterations on these properties was also examined. A cordierite solid solution was formed when R = Ni, Cu, Sr, or Ba; however, an additional phase emerged when R = Zn, Sr, or Ca. The complete substitution influenced the relative dielectric constant of Mg 1.8 R 0.2 Al 4 Si 5 O 18 due to the ionic polarizability and the average ionic property of the R ion. The Q × f value was found to be related to the crystal lattice energy, while the τ f value was primarily affected by octahedral distortion. The appearance of a secondary phase altered the primary factors influencing the dielectric properties of the Mg 1.8 R 0.2 Al 4 Si 5 O 18 ceramics. Among the substitutions tested, Mg 1.8 Ni 0.2 Al 4 Si 5 O 18 exhibited superior microwave dielectric properties with ε r = 4.64, Q × f = 44,770 GHz, and τ f = −32 ppm/°C. [ABSTRACT FROM AUTHOR]

In this report, rare-earth-free Mg4Nb2O9:Mn4+ phosphors were obtained through a high-temperature solid-state reaction. This work aims to investigate the photoluminescence properties of Mg4Nb2O9:Mn4+ phosphors and the temperature sensitive performance of the optimized phosphor. The crystal structure and lattice parameters as well as the effects of the dopant ions on the host structure were investigated. It should be noted that the Mg4Nb2O9 crystal is in a trigonal system P3¯c1. The as-prepared phosphors exhibited good thermal sensitivity, and the relative sensitivity of the optimal Mg4Nb2O9:0.004Mn4+ phosphor was calculated to be 0.48% K−1, allowing it to activate optical temperature sensing applications. [ABSTRACT FROM AUTHOR]

In this paper, 4. 2% ytterbium-doped calcium niobium gallium garnet (Yb∶Ca3 (NbGa)5 O12) crystals with diameter of 2 inch (1 inch =2. 54 cm) were grown by Bridgman method. The obtained crystals were intact and free of visible defects. Crystal structure was determine by XRD, which reveals that the crystal belongs to the cubic crystal system with lattice parameters a = b = c =12. 493 Å. The crystals were oriented and cut to obtain some (420) plane wafers with dimensions of 10 mm ×10 mm ×1 mm. These wafers were double-side polished to obtain the final samples. The performance of the samples was characterized through X-ray diffraction, ultraviolet-visible spectrophotometer, and fluorescence spectroscope. The results show that the rocking curve of the crystal has a full width at half maximum (FWHM) of 43″, and the transmittance reaches 80% in the near-infrared wavelength range. At 935 nm, FWHM of the absorption peak is 47. 15 nm and absorption crosssection is 1. 53 ×10 -20 cm2. When excited with a 980 nm laser, an emission peak was observed at 1 031 nm, corresponding to the transition of Yb3 + from the excited state 2 F5/2 to the ground state 2 F7/2. [ABSTRACT FROM AUTHOR]

The use of tris(4-aminophenyl)amine (TAPA) as central to the synthesis of both polyimines and polyimides and covalent organic frameworks and inorganic cages, among others, has grown in the last few years. The resulting materials exhibit high performance in their area of application. In this contribution, the crystal structures of two TAPA derivatives, triethyl (nitrilotris(benzene-4,1-diyl))tricarbamate (1) and triethyl 2,2′,2″-((nitrilotris(benzene-4,1-diyl))tris(azanediyl))tris(2-oxoacetate) (2), are described. The molecular and supramolecular structures of both compounds were compared between them and with analogous compounds. The analyses of their vibrational and 13C-CPMAS NMR spectroscopies, as well as their thermal stability, were included and corelated with the crystal structure. Hirshfeld surface analysis on the crystal structures of both TAPA derivatives revealed the stabilization of the crystal network via the amide N—H∙∙∙O interactions of dispersive nature in the carbamate, whereas dispersive carbonyl–carbonyl interactions also played a competitive role in the supramolecular arrangement of the oxamate. Interaction energy DFT calculations performed at the B3LYP/6-31G(d,p) level allowed us to estimate the energy contributions and nature of several interactions in terms of the stability of both crystal lattices. [ABSTRACT FROM AUTHOR]

The equimolar reaction between 1,9-bis(N,N-dimethylaminomethyl)-5,5′-diphenyldipyrromethane, H2L1 or 1,9-bis(3,5-dimethylpyrazolylmethyl)-5,5′-diethyldipyrromethane, H2L2 and [NiCl2(DME)] in the presence of KH yielded the neutral mononuclear nickel(II) complexes [Ni(L1)-κ4N,N,N,N], 1 and [Ni(L2)-κ4N,N,N,N], 2, respectively. Their X-ray structures revealed the formation of triple chelation by the ligand in both structures with quite different nickel(II)-surrounded square planar geometries owing to the steric difference between –NMe2 and 3,5-dimethylpyrazolyl groups. While the –NMe2 group substituted ligand L1 afforded nickel complex 1 with a plane of symmetry, 3,5-dimethylpyrazole substituted L2 rendered helical chirality in the structure of complex 2. Both the enantiomers (Δ and Λ) of complex 2 were observed in the crystal lattice. Their solution state behaviors were consistent with the solid-state structures as monitored by 1H NMR spectroscopy. Both the enantiomers of complex 2 were present in a dynamic equilibrium in solution and studied by variable temperature 1H NMR spectroscopy. Similar to the chiral complex, the corresponding ligand H2L2 also exhibited chirality as shown by its crystal structure and the two ligand enantiomers participated in a very fast dynamic interconversion, which became slower upon metalation. [ABSTRACT FROM AUTHOR]

In this work, the structure of a CrMnFeCoNiCu high-entropy alloy (HEA) film deposited by magnetron evaporation on a steel substrate is studied. It is established that the phase content of the CrMnFeCoNiCu HEAs is determined by a superposition of contributions from equiatomic simple cubic lattices of the CrMnFeCoNiCu composition (Struct-26 and Struct-278) with space group P1. It is found that the contributions of the diffraction patterns from the reference lattices to the integral intensity are 0.66 and 0.29, respectively. For simple cubic lattices Struct-26 and Struct-278, the full structural information (the lattice parameters, coordinates of atoms, spatial groups, and occupancies) is derived. It is established that the CrMnFeCoNiCu HEA is a stable compound, which is confirmed by calculations of the mixing energy for the convex Hull model. [ABSTRACT FROM AUTHOR]

The key objective of this study is to determine the effect of interphase boundaries, the formation of which is caused by the variation of Li2ZrO3/MgLi2ZrO4 phases in lithium-containing ceramics based on lithium metazirconate, on the resistance to near-surface layer destruction processes associated with irradiation with He2+ ions. During the observation of the deformation effects that have an adverse impact on the volumetric swelling of the near-surface layers of ceramics, the thermal expansion factor caused by high-temperature irradiation was considered, simulating conditions as close as possible to the operating conditions of these materials as blankets for tritium propagation. During the studies conducted, it was established that an elevation in the contribution of MgLi2ZrO4 in the composition of ceramics leads to a rise in resistance to deformation swelling caused by structural distortions of the crystal lattice, due to a decrease in the effect of thermal expansion, alongside the presence of interphase boundaries. The established dependencies of the change in the hardness of the near-surface layer of the studied ceramics made it possible to establish the kinetics of softening caused by the deformation distortion of the crystalline structure, as well as to determine the relationship between volumetric swelling and softening (change in hardness) and a decrease in crack resistance (change in the value of resistance to single compression). [ABSTRACT FROM AUTHOR]

The surface chemistry of pyrrhotites from intact particles directly collected from asteroid (162173) Ryugu was investigated by micro-Raman spectroscopy. The Raman peak characteristic to pyrrhotite was observed at around 115 cm−1 in Ryugu pyrrhotites, similar to freshly cleaved surfaces of terrestrial pyrrhotites. Additional Raman bands centered at around 220, 275, and 313 cm−1 with broadened features were also detected from the Ryugu pyrrhotites. The set of Raman bands at 220 and 275 cm−1 was assigned to typical Fe-S stretching vibrations of ν 2 (225 cm−1) and ν 1 (275 cm−1). These bands are not clearly observed in bulk crystals of pyrrhotite but appear in its nanoparticulate phase. These bands are ordinarily seen in amorphous monosulfides that formed under low oxygen fugacity (f O 2) conditions in nature, indicating that the structural alteration of pyrrhotite surfaces occurred heterogeneously on the nanoscale under low f O 2 conditions. Further, the Raman band at 313 cm−1 was attributed to a characteristic tetrahedral bonding of Fe(III) in the lattice of FeII 1-3x FeIII 1-2x S, followed by the local breakdown of the crystal lattice structures from planar bonding with Fe(II). In addition, some areas of the Ryugu pyrrhotite grains showed corroded structures with iridescence. Furthermore, assemblages of magnetite particles were also preferentially observed on small areas of the likely-dissolved pyrrhotite crystals in phyllosilicate matrices. These characteristic features in the Raman spectra and in corroded structures of Ryugu pyrrhotites record changes in the local environmental conditions via aqueous alteration. The corrosion of pyrrhotite crystals followed by the preferential formation of magnetite particles by asteroidal water is the likely product of dissolution of Fe(II) from the pyrrhotite surface and its oxidative precipitation in microchemical environments on the Ryugu parent body. [ABSTRACT FROM AUTHOR]

Polymorphic control is vital for the quality control of pharmaceutical crystals. Here, we investigated the relationship between the hydrate and anhydrate polymorphs of a monoacylglycerol acyltransferase 2 inhibitor (S-309309). Solvent evaporation and slurry conversion revealed two polymorphs, the hydrate and the solvate. The solvate was transformed into the hydrate by heating. X-ray powder diffraction demonstrated that the hydrate was transformed into an anhydrate via an intermediate state when heated. These crystal forms were confirmed under controlled humidity conditions; the presence of the anhydrate, the intermediate hydrate, or the hydrate depended on the relative humidity at 25 °C. The stoichiometry of S-309309 in water in the hydrate form was 4:1. The hydrates and anhydrates exhibited similar crystal structures and stability. The water of hydration in the intermediate hydrate was 0.1–0.15 mol according to the dynamic vapor sorption profile. The stability and dissolution profile of the anhydrate and hydrate showed no significant change due to similar crystal lattices and quick rehydration of the anhydrate. A mechanism for the reversible crystal transformation between the anhydrate and pseudo-polymorphs of the hydrate was discovered. We concluded that S-309309 causes a pseudo-polymorphic transformation; however, this is not a critical issue for pharmaceutical use. [ABSTRACT FROM AUTHOR]

Molecular structures of 5-chloro-7-azaindole-3-carbaldehyde (5Cl7AICA) and 4-chloro-7-azaindole-3-carbaldehyde (4Cl7AICA) were investigated using infrared and Raman spectroscopy supported by density functional theory (DFT) calculations. Theoretical studies were carried out with three DFT methods, which include dispersion corrections: B3LYP-D3, PBE0-D3, and ωB97X-D. A single-crystal X-ray diffraction analysis was performed for 5Cl7AICA. The compound crystallizes in the monoclinic system, space group P21/c, with lattice parameters a = 3.82810(12) Å, b = 12.7330(3) Å, c = 15.9167(5) Å, and β = 94.539(3)°, with Z = 4. Within the crystal lattice, 5Cl7AICA molecules form dimers via dual and strong N1–H1⋅⋅⋅N7′ hydrogen bonds, accompanied by other intermolecular interactions. In the DFT calculations, two types of dimers of the investigated molecules were analyzed: dimer 1, which is present in the crystal structure of 5Cl7AICA, and dimer 2 displaying a 180° rotation of the aldehyde group compared to dimer 1. Computational results indicate that dimer 1 is more stable than dimer 2 for 5Cl7AICA, whereas dimer 2 is more stable than dimer 1 for 4Cl7AICA molecules. Furthermore, experimental and theoretical vibrational spectra were examined to elucidate the influence of internal rotation of the aldehyde group on spectroscopic properties. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this work is to study the effect of sintering modes, especially the sintering temperature, on the crystal lattice parameters and the morphology of the ZrO2-nY2O3 (n = 3-8 mol%) ceramic microstructure components in relation to corresponding fracture micromechanisms. Design/methodology/approach: The series of ZrO2-nY2O3 (n = 3-8 mol%) ceramics were sintered in an argon atmosphere at temperatures 1450°C, 1500°C, 1550°C, and 1600°C. The cross-sectional surfaces of samples were prepared for microstructure analysis using a grinding and polishing Struers Tegramin machine. Young's ceramics modulus values were determined using an ultrasonic flaw detector Panametrics EPOCH III 2300. The samples' density and porosity were determined by the Archimedes' method. Scanning electron microscopes Hitachi SU3900 and Carl Zeiss EVO-40XVP were used to analyse the microstructure and fracture surface morphology of samples. For estimating chemical compositions in an energy-dispersive X-ray spectroscopy mode, an INCA ENERGY 350 spectrometer was utilized. Microhardness measurement was performed on a NOVOTEST TC-MKB1 microhardness tester. The fracture toughness of the material was estimated using a single-edge notch beam (SENB) test and the Vickers indentation test. Both the flexural strength and SENB tests were performed under threepoint bending using a UIT STM 050 test machine. All mechanical tests were carried out in air at a temperature of 20°C. Findings: Optimal sintering modes for a variety of YSZ ceramic compositions are found, taking into account the combined effect of the sintering temperature and a percentage of Y2O3, which resulted in a specified balance of cubic, tetragonal, and monoclinic zirconia phases, an optimal microstructure features, and the implementation of high-energy fracture micromechanisms responsible for high strength and fracture toughness of YSZ ceramics. Research limitations/implications: To study the behaviour of YSZ ceramics in the operating atmosphere, their microhardness, flexural strength, and fracture toughness should be evaluated under the operating temperature and pressure conditions. Practical implications: Based on the research performed, it is possible to design the microstructure of YSZ ceramic with the necessary physical and mechanical properties to provide high reliability of ceramic products in various industry branches. Originality/value: The balance of cubic, tetragonal, and monoclinic zirconia phases, as well as the crystal lattice parameters change, was determined for YSZ ceramics stabilized with the various amounts of yttria, and it was linked to their mechanical behaviour; the Vickers indentation method and SENB method were used to estimate crack growth resistance of YSZ ceramics, and an appropriate fracture micromechanism was found. [ABSTRACT FROM AUTHOR]

The long-range periodic atomic arrangement or the lack thereof in solids typically dictates the magnitude and temperature dependence of their lattice thermal conductivity (κlat). Compared to crystalline materials, glasses exhibit a much-suppressed κlat across all temperatures as the phonon mean free path reaches parity with the interatomic distances therein. While the occurrence of such glass-like thermal transport in crystalline solids captivates the scientific community with its fundamental inquiry, it also holds the potential for profoundly impacting the field of thermoelectric energy conversion. Therefore, efficient manipulation of thermal transport and comprehension of the microscopic mechanisms dictating phonon scattering in crystalline solids are paramount. As quantized lattice vibrations (i.e., phonons) drive κlat, atomistic insights into the chemical bonding characteristics are crucial to have informed knowledge about their origins. Recently, it has been observed that within the highly symmetric 'averaged' crystal structures, often there are hidden locally asymmetric atomic motifs (within a few Å), which exert far-reaching influence on phonon transport. Phenomena such as local atomic off-centering, atomic rattling or tunneling, liquid-like atomic motion, site splitting, local ordering, etc., which arise within a few Å scales, are generally found to drastically disrupt the passage of heat carrying phonons. Despite their profound implication(s) for phonon dynamics, they are often overlooked by traditional crystallographic techniques. In this review, we provide a brief overview of the fundamental aspects of heat transport and explore the status quo of innately low thermally conductive crystalline solids, wherein the phonon dynamics is majorly governed by local structural phenomena. We also discuss advanced techniques capable of characterizing the crystal structure at the sub-atomic level. Subsequently, we delve into the emergent new ideas with examples linked to local crystal structure and lattice dynamics. While discussing the implications of the local structure for thermal conductivity, we provide the state-of-the-art examples of high-performance thermoelectric materials. Finally, we offer our viewpoint on the experimental and theoretical challenges, potential new paths, and the integration of novel strategies with material synthesis to achieve low κlat and realize high thermoelectric performance in crystalline solids via local structure designing. [ABSTRACT FROM AUTHOR]

This article presents crystal structures of chalcogenadiazolecarboxylic acids bearing both a hydrogen and a chalcogen bond donor. The selected molecules varied in the size of the aromatic unit, the chalcogen atom and/or the position of the carboxyl group in the core structure. The most common synthons in their lattice are R 22 (8) self-complementary acid dimers or four-membered [Ch⋯N]2 rings. Supramolecular synthons where chalcogenadiazole moieties interact with the carboxyl group were also identified. Both ESP calculations and experimental data showed that all the studied molecules adopted flat conformations, but only in the case of three crystal structures were flat sheets observed. To assess the contribution of hydrogen and chalcogen bonds to the stabilization of the crystal structure, crystal lattice energy calculations were performed. [ABSTRACT FROM AUTHOR]

Near-white emission phosphors of the Bi3+/Sm3+ co-doped double-perovskite Ca 2 YTaO 6 were successfully prepared via a simple solid-state reaction. The crystal structures and lattice parameters as functions of doping ion type and its content were analyzed. Note that all the prepared samples have the monoclinic structure with the space group of P 21/n (14). Their lattice parameters were enlarged with the increment of doping ion content since the Y3+ ion with the smaller radius was substituted by the Bi3+ and Sm3+ ions. The photoluminescence (PL) properties of single Bi3+-doped and Bi3+/Sm3+ co-doped Ca 2 YTaO 6 phosphors were fully investigated in terms of PL emission spectrum, emission intensity, energy transfer mechanism, chromaticity coordinate, decay curve, thermal stability, and internal quantum yield. Interestingly, the Ca 2 YTaO 6 :0.015Bi3+/0.07Sm3+ phosphor exhibited a high quantum yield (70.71%). Furthermore, the relative sensitivity based on the dual-emission centers (Bi3+ and Sm3+) was also analyzed. It is demonstrated that high-efficiency near-white Ca 2 YTaO 6 :Bi3+/Sm3+ phosphor with good sensing properties is expected to be a candidate in the field of optical thermometry. [ABSTRACT FROM AUTHOR]

Large-pore protein crystals (LPCs) are an emerging class of biomaterials. The inherent diversity of proteins translates to a diversity of crystal lattice structures, many of which display large pores and solvent channels. These pores can, in turn, be functionalized via directed evolution and rational redesign based on the known crystal structures. LPCs possess extremely high solvent content, as well as extremely high surface area to volume ratios. Because of these characteristics, LPCs continue to be explored in diverse applications including catalysis, targeted therapeutic delivery, templating of nanostructures, structural biology. This Feature review article will describe several of the existing platforms in detail, with particular focus on LPC synthesis approaches and reported applications. [ABSTRACT FROM AUTHOR]

The synthesis and structural characterization of new "2+1" mixed ligand fac-[Re(CO)3(OO)(L)] and Re(CO)2(OO)(L)2 complexes are reported herein. Maltol and kojic acid were chosen as bidentate OO ligands, while imidazole, isocyanocyclohexane or triphenylphosphine were selected as the monodentate ligands. The synthesis of the rhenium complexes was based on the reaction of [NEt4]2[Re(CO)3Br3] with maltol and kojic acid to generate the intermediate aqua complex fac-[Re(CO)3(OO)(H2O)], followed by the replacement of the labile aqua ligand by the monodentate ligand. Structural characterization of all Re complexes was established by NMR and IR spectroscopies, as well as two of them by single-crystal X-ray crystallography, revealing distorted octahedral geometry around the Re center. In the crystal lattice, the complexes form supramolecular networks due to the development of intermolecular interactions of the N-H⋯O, C-H⋯O and C-H⋯π type. [ABSTRACT FROM AUTHOR]

The Li 3 LaMg 2 TiO 7 :Mn4+ fluorescent ceramics were synthesized via the high-temperature solid-phase method and characterized using XRD analysis and spectral properties evaluation. Under the excitation of a 375 nm LED, the red emission at 711 nm was detected. Interestingly, the quantum efficiency of this red light is closely correlated with the spatial distribution of the ceramics. The quantum efficiency of the ceramic interior reached 23.6 %, while on the outer upper surface, it significantly soared to 93.1 %, representing an almost fourfold disparity. Furthermore, the luminous efficiency is shape-dependent, with a cylinder exhibits higher efficiency than sphere or cuboid. For samples of the same shape, the upper surface efficiency surpasses that of the side and bottom surfaces. Based on an analysis of crystal structure and energy level diagrams, we attribute this phenomenon to two factors: firstly, ceramic shape-induced distortion of crystal lattice squeezes numerous electrons on outer surfaces into adjacent energy wells resulting in a Q-switching effect; secondly, the temperature gradient between the upper and lower regions induces convective airflow, leading to variations in electron distribution across the upper and lower surfaces, thereby resulting in disparate luminous efficiencies. This spatially dependent luminescence phenomenon holds potential for exploring high-efficiency fluorescent materials. [ABSTRACT FROM AUTHOR]

Imaging scaffolds composed of designed protein cages fused to designed ankyrin repeat proteins (DARPins) have enabled the structure determination of small proteins by cryogenic electron microscopy (cryo‐EM). One particularly well characterized scaffold type is a symmetric tetrahedral assembly composed of 24 subunits, 12 A and 12 B, which has three cargo‐binding DARPins positioned on each vertex. Here, the X‐ray crystal structure of a representative tetrahedral scaffold in the apo state is reported at 3.8 Å resolution. The X‐ray crystal structure complements recent cryo‐EM findings on a closely related scaffold, while also suggesting potential utility for crystallographic investigations. As observed in this crystal structure, one of the three DARPins, which serve as modular adaptors for binding diverse 'cargo' proteins, present on each of the vertices is oriented towards a large solvent channel. The crystal lattice is unusually porous, suggesting that it may be possible to soak crystals of the scaffold with small (≤30 kDa) protein cargo ligands and subsequently determine cage–cargo structures via X‐ray crystallography. The results suggest the possibility that cryo‐EM scaffolds may be repurposed for structure determination by X‐ray crystallography, thus extending the utility of electron‐microscopy scaffold designs for alternative structural biology applications. [ABSTRACT FROM AUTHOR]

An organic 5‐methyl‐1H‐imidazole‐3‐ium‐4‐carboxybutanoate (5MIC) co‐crystal is grown by slow evaporation solution growth technique (SEST) at room temperature. The 5MIC is synthesized using 4‐methylimidazole and glutaric acid in a 1:1 ratio using methanol as a solvent. The 5MIC crystal lattice parameters are identified using single‐crystal X‐ray diffraction analysis. The experimental X‐ray diffraction (XRD) and DFT structural parameter values have good correlations. The intermolecular interactions of the 5MIC crystal are found using Hirshfeld surface and 2D fingerprint plots. The computed C–N stretching vibration of the imidazole ring is observed at 1498, 1233, and 1064 cm−1. The HOMO is located on 4‐methylimidazole moiety of 5MIC molecule. Densities of state are used to find out the molecular orbital compositions of the 5MIC molecule. Mulliken analysis shows that the C13 (−0.86) atom has the lowest negative charge. The MEP surface color coded of 5MIC lies between 7.950 e−3 and −7.950 e−3. The 5MIC molecule has four types of intermolecular transitions. The first‐order hyperpolarizability (β) value of 5MIC molecule is 5.48×10−30 esu. The 5MIC crystal is thermaly stable up to 146 °C. The photoluminescence emission is observed from 400 to 600 nm. The 5MIC crystal shows SHG characteristics. [ABSTRACT FROM AUTHOR]

The B-factor, also known as the atomic displacement parameter, is a fundamental metric in crystallography for quantifying the positional flexibility of atoms within crystal lattices. In structural biology, various developments have expanded the use of B-factors beyond conventional crystallographic analysis, allowing for a deeper understanding of protein flexibility, enzyme manipulation, and an improved understanding of molecular dynamics. However, the interpretation of B-factors is complicated by their sensitivity to various experimental and computational factors, necessitating rigorous rescaling methods to ensure meaningful comparisons across different structures. This article provides an in-depth description of rescaling approaches used for B-factors. It includes an examination of several methods for managing conformational disorder and selecting the atom types required for the analysis. [ABSTRACT FROM AUTHOR]

In this work, samples of single-crystalline silicon doped with tin were studied using X-ray diffraction and electron microscopy. It has been established that at a scattering angle of 2θ ≈ 36.6° in the X-ray diffraction patterns of n-Si and Si samples, structural reflections (110) of the corresponding SiO2 nanocrystallites with lattice parameters a = b = 0,4936 нм и c = 0,5212 nm and c = 0.5212 nm, belonging to the hexagonal crystal lattice and space group P321. The formation of tin nanocrystallites with sizes of 9.1 and 8 nm in the near-surface regions of the Si matrix crystal lattice was discovered. [ABSTRACT FROM AUTHOR]

Hard coatings are in constant development and evolution, so the generation of new quaternary systems is of great importance. Thus, this research studies the influence of the incorporation of Vanadium atoms into the FCC structure of TiCN, to conform to a quaternary system (TiVCN), which there is very little information so far. The structural analysis evidenced that this quaternary system maintains the same FCC crystal structure as TiCN, and that this structural configuration is in agreement with the models proposed by Hume-Rothery, in which the Titanium and Vanadium atoms randomly occupy the Wyckoff 4a positions and the Carbon and Nitrogen atoms occupy the Wyckoff 4b position. Since Ti and V atoms have a difference in atomic radius, they cause a distortion of the crystal lattice, which will modify the mechanical properties. Experimental results determined a 60 % decrease in roughness, and a 26 % increase in hardness for the TiVCN system compared to TiCN. Thus, this new quaternary system will be a better option to be implemented as protective coatings compared to conventional systems such as TiCN. [ABSTRACT FROM AUTHOR]

The crystal structure of MeN nitrides, existing in the surface layers of PcBN composites of cBN-{TiN, ZrN, HfN, VN, NbN}–Al systems (composition, vol. %: cBN: MeN: Al as (60:35:5, vol. %) sintered at high pressure and high temperature (HPHT, 7.7 GPa, 1600-2450 °C), was studied in detail using the X-ray diffraction structural analysis method. It was shown that the crystal structure of each MeN nitride belongs to the modified NaCl type structure with an additional position partially filled by the nitrogen atoms. The presence of such a position leads to a certain excess of nitrogen on the sample's surface, the source of which is nitrides from the depth of the composite. It is shown that the diffusion of nitrogen atoms through defects and lattice sites of MeN crystal lattices from the bulk to the surface of composite plays an important role in the formation of crystal structures of MeN nitrides at the biothermal conditions. Using the results of X-ray diffraction structural calculations as reference values, the main parameters of this diffusion process (activation energy and rate constant) were determined for cBN-{TiN, HfN, VN, NbN}-Al composites. It is shown that the activation energy of diffusion increases in HfN → TiN → VN → NbN series and correlates with the formation enthalpy of each MeN nitrides. [ABSTRACT FROM AUTHOR]

The supramolecular organization of organic salts has been widely researched, revealing recurring patterns in crystalline lattices that describe their supramolecular properties. In recent years, our research group has underscored the importance of considering the crystalline structures as a whole, incorporating all the necessary energetic and topological information for a comprehensive understanding of the crystalline system. Given this context, we investigated a series of ammonium mono- and dicarboxylate salts (1–12) to determine whether subtle structural modifications in the anionic organic component lead to relevant energy and topology changes in the crystalline lattice. To achieve this, we selected structures whose carboxylate anion only possesses an alkyl chain and is devoid of other functional groups. The ammonium cation (NH4+) was fixed to determine the effect of variations in the alkyl chains of the selected mono- and dicarboxylates, such as length and degree of unsaturation. Additionally, probable crystallization mechanisms were proposed to elucidate some of the topological and energetic aspects involved in the crystallization of these compounds. Destabilizing interactions were observed in 10 crystalline structures, and the MEP data showed that the most destabilizing interactions occur by the proximity of portions with the same type of charge. Some dimers have unexpectedly low intermolecular interaction energies despite having large contact areas. Based on these data we demonstrate the additivity of intermolecular interactions, that is, the low intermolecular interaction energy in these dimers is the result of the sum of destabilizing energies and stabilizing energies. The cluster energy efficiency data revealed that most crystal lattices display typical characteristics of uncharged organic compounds. The proposed crystallization mechanisms showed a gradual increase in nucleus complexity in the initial stages and the total number of nucleation stages, resulting in five main patterns: monomer → 1D → 3D (1–2), monomer → dimer → 2D → 3D (3), monomer → 1D → 2D → 3D (4–5), monomer → dimer → 3D (6), and monomer → 2D → 3D (7–12). [ABSTRACT FROM AUTHOR]

Meclizine (Antivert, Bonine) is a first‐generation H1 antihistamine used in the treatment of motion sickness and vertigo. Despite its wide medical use for over 70 years, its crystal structure and the details of protein‐drug interactions remained unknown. Single‐crystal X‐ray diffraction (SC‐XRD) is previously unsuccessful for meclizine. Today, microcrystal electron diffraction (MicroED) enables the analysis of nano‐ or micro‐sized crystals that are merely a billionth the size needed for SC‐XRD directly from seemingly amorphous powder. In this study, MicroED to determine the 3D crystal structure of meclizine dihydrochloride is used. Two racemic enantiomers (R/S) are found in the unit cell, which is packed as repetitive double layers in the crystal lattice. The packing is made of multiple strong N‐H‐Cl− hydrogen bonding interactions and weak interactions like C‐H‐Cl− and pi‐stacking. Molecular docking reveals the binding mechanism of meclizine to the histamine H1 receptor. A comparison of the docking complexes between histamine H1 receptor and meclizine or levocetirizine (a second‐generation antihistamine) shows the conserved binding sites. This research illustrates the combined use of MicroED and molecular docking in unraveling elusive drug structures and protein‐drug interactions for precision drug design and optimization. [ABSTRACT FROM AUTHOR]

Substrates are essential in thin‐film deposition, yet they do not always meet the requirements of a given application. For example, they might be prohibitively expensive or not even available with the necessary crystal lattice structures. This paper introduces the innovative concept of "vector substrates," where the template layer for thin‐film growth, referred to as vector, is chemically and crystallographically independent of the bulk of the substrate. This approach reduces material costs and offers unparalleled flexibility. The fabrication of vector substrates leverages thin‐film membrane technology. The process begins by growing a template layer on a parent substrate. The template layer is then transferred onto a carrier substrate, thereby generating the vector substrate. Vector substrate technology enables researchers and manufacturers with thin‐film deposition facilities to fabricate optimized substrates that would otherwise be difficult to obtain using bulk single‐crystal growth technology. An in‐depth discussion of the benefits and limitations of vector substrates compared with traditional substrates is provided. Furthermore, the practical viability of the concept is demonstrated by fabricating sets of vector substrates. Although this concept is still in its infancy, it has a significant potential to complement conventional substrates for future advancements in substrate technology and thin‐film deposition. [ABSTRACT FROM AUTHOR]

A new bis amide N-(4-methylphenyl)-2-(3-nitrobenzamide) benzamide was synthesized from a ring-opening reaction of 2-(3-nitrophenyl)-4H-benzoxazin-4-one, with 4-methyl aniline in a shorten reaction time (1.0 min) and characterized using different spectroscopic techniques (FT-IR, 1H-NMR, 13C-NMR) and single-crystal X-ray diffraction (XRD). In the crystal lattice, the molecules are linked by N-H···O and C-H···O hydrogen bonds. The Hirshfeld surface analysis mapped over shape index, curvedness indices, dnorm revealed strong H...H and H...O/O...H and intermolecular connections a key contributors to crystal packing structure. Density functional theory (DFT) calculations were applied with B3LYP/6-311G(d) level to provide theoretical data along with HOMOLUMO electronic energy with the MEP map. [ABSTRACT FROM AUTHOR]

The mechanical α-relaxation of polyethylene was studied under different testing conditions and distinct polyethylene sheets. The condition of 2.5 mm thickness and 3 ℃/min was in favor of observing and analyzing the α-relaxation. The α2-relaxation peak in tan δ curves disappears under the high-frequency condition of 10 Hz since the α2-relaxation temperature is higher than melting temperature, which provide the support for the explanation on the disappearance of the α2-relaxation caused by crystalline properties. The influences of thermal history for the sheets of linear and branched polyethylene, as well as melting index for linear polyethylene on α-relaxation can be attributed to both lamella thickness and crystallinity. The higher lamella thickness and crystallinity, the more obviousness and higher temperature of α1-relaxation, as well as the higher temperature of α2-relaxation or cause the disappearance of α2-relaxation peak. The variation of multiple α-relaxations was interpreted using a microcrystalline structure and macro-crystallinity. The chain motion in amorphous being more restricted and the chain motion in crystal lattices requiring more energy contribute to the temperature increasing of α1- and α2-relaxation, respectively. The higher remaining crystallinity during the premelting process causes the increase in the α2-relaxation temperature. [ABSTRACT FROM AUTHOR]

One of the classes of the kinetic phase-field model in the form of the two-mode hyperbolic phase-field crystal model (modified PFC model) is used for the study of the noise effect of the crystalline structure. Special attention is paid to the origin of the defect's microstructure in the crystalline honeycomb lattice due to induced colored noise. It shows that the noise–time correlation coefficient τ ζ , comparable to the diffusion time, enhances the grain boundary mobilities. Instead, a small spatial correlation coefficient, λ ζ , close to the first lattice parameter of the honeycomb crystal, stabilizes the structure. The finite non-zero value of the relaxation time τ for the atomic flux significantly slows the local relaxation of the fluctuated field and leads to the grains' fragmentation and formation of the disordered phases. The obtained results are applicable to the hexagonal atomic structures and, in particular, to honeycomb crystals, such as boron nitride, in which the lattice defects might be simulated through the induced colored noise. [ABSTRACT FROM AUTHOR]

Self-assembly of isotropically interacting particles into desired crystal structures could allow for creating designed functional materials via simple synthetic means. However, the ability to use isotropic particles to assemble different crystal types remains challenging, especially for generating low-coordinated crystal structures. Here, we demonstrate that isotropic pairwise interparticle interactions can be rationally tuned through the design of DNA shells in a range that allows transition from common, high-coordinated FCC-CuAu and BCC-CsCl lattices, to more exotic symmetries for spherical particles such as the SC-NaCl lattice and to low-coordinated crystal structures (i.e., cubic diamond, open honeycomb). The combination of computational and experimental approaches reveals such a design strategy using DNA-functionalized nanoparticles and successfully demonstrates the realization of BCC-CsCl, SC-NaCl, and a weakly ordered cubic diamond phase. The study reveals the phase behavior of isotropic nanoparticles for DNA-shell tunable interaction, which, due to the ease of synthesis is promising for the practical realization of non-close-packed lattices. [ABSTRACT FROM AUTHOR]

The current work elicits a simple and efficient synthesis method of a series of imidazole through reaction of hydrazine with three aromatic aldehydes (3,5-di-tert-butylsalicylaldehyde, 3-tert-butylsalicylaldehyde and 5-tert-butylsalicylaldehyde). The synthesized compounds 1–3 were characterized by 1H and 13C NMR techniques and confirmed by single-crystal X-ray diffraction. The crystal structural analysis shows that the compounds 1 (CCDC 1497574) and 2 (CCDC 2235333) crystallizes in the triclinic crystal lattice. The presence of O and N atoms as potential acceptors for classical hydrogen bonds, allows us to have the intramolecular and intermolecular interaction in each crystal as an N–H and O–H bond. These generate a two-dimensional network. Two kinds of π–π stacking interactions were observed between consecutive 2D networks, imidazole-imidazole 1 and imidazole-phenyl/phenyl-phenyl interactions 2. Further, the molecular docking of active compounds site and the human MDM2 protein showed that the tested compounds indicated good anticancer activity. [ABSTRACT FROM AUTHOR]

Purpose: To synthesize and characterize new cocrystals of berberine chloride (BCl) for potential pharmaceutical tablet formulation. Methods: Solutions of BCl with each of three selected cocrystal formers, catechol (CAT), resorcinol (RES), and hydroquinone (HYQ) were slowly evaporated at room temperature to obtain crystals. Crystal structures were solved using single crystal X-ray diffraction. Bulk powders were characterized by powder X-ray diffraction, thermogravimetric-differential scanning calorimetry, FTIR, dynamic moisture sorption, and dissolution (both intrinsic and powder). Results: Single crystal structures confirmed the formation of cocrystals with all three coformers, which revealed various intermolecular interactions that stabilized crystal lattices, including O–H···Cl− hydrogen bonds. All three cocrystals exhibited better stability against high humidity (up to 95% relative humidity) at 25 ℃ and higher intrinsic and powder dissolution rates than BCl. Conclusion: The enhanced pharmaceutical properties of all three cocrystals, as compared to BCl, further contribute to the existing evidence that confirms the beneficial role of cocrystallization in facilitating drug development. These new cocrystals expand the structure landscape of BCl solid forms, which is important for future analysis to establish a reliable relationship between crystal structure and pharmaceutical properties. [ABSTRACT FROM AUTHOR]

Chirality was traditionally considered a binary property of periodic lattices and crystals. However, the classes of two‐dimensional lattices modulo rigid motion form a continuous space, which was recently parametrized by three geographic‐style coordinates. The four non‐oblique Bravais classes of two‐dimensional lattices form low‐dimensional singular subspaces in the full continuous space. Now, the deviations of a lattice from its higher symmetry neighbors can be continuously quantified by real‐valued distances satisfying metric axioms. This article analyzes these and newer G‐chiral distances for millions of two‐dimensional lattices that are extracted from thousands of available two‐dimensional materials and real crystal structures in the Cambridge Structural Database. [ABSTRACT FROM AUTHOR]

Series of ceria-zirconia (CZ)-based nano-materials with a d50 in the range of 0.2 to 1.3 microns were made using the jar milling, Eiger milling, and steam jet milling (SJM) techniques. The effect of the milling conditions on the morphology and textural properties was studied. High-energy steam jet milling in a quasi-hydrothermal environment (with potential local temperature spikes over 500 °C) significantly impacted the CZ crystal structure by inducing lattice distortions. It was shown that the acquired lattice stress resulted in a significant increase in oxygen mobility, which was manifested by a TPR-H2 Tmax shift from 450–550 to 150–250 °C. CZ materials with fast oxygen mobility are metastable phases, and re-slurring nano-CZ powders in water and impregnation with precious metals had stabilizing effects on fast oxygen mobility. Efficiently enhancing the CZ redox activity milling process took place in the following order: Steam jet milling > Eiger milling > jar milling. [ABSTRACT FROM AUTHOR]

Tb3+-ion-doped metal phosphates (YPO4, LaPO4, CePO4 and GdPO4) nanoparticles (NPs) were synthesized by a urea-supported thermal decomposition method. A comparative analysis was presented to inspect the influence of the host lattice on crystal structure, optical and luminescent properties of the doped Tb3+ ion. X-ray diffraction (XRD) results show the rhabdophane-type hexagonal phase of all lanthanide phosphate (LnPO4) NPs with an average particles size 12.8, 14.9, 18 and 19.5 nm for the YPO4:Tb, LaPO4:Ce/Tb, CePO4:Tb and GdPO4:Tb NPs, respectively. Fourier transforms infrared (FTIR) spectra illustrated the characteristics of crystal and surface build phosphate (PO43–) ion and hydroxyl (OH) vibrational modes, respectively. Absorption spectra were measured to determine the aqueous dispersibility, colloidal stability and charge transfer absorption transitions of the host and guest ions. The absorption edge and bandgap energies were greatly affected in Ce3+-ion-containing NPs because of the high absorbance in the visible region. Upon irradiation of all samples from the similar ultraviolet range 368 nm, the emission efficiency of the 5D4→7F5 of the YPO4:Tb NPs was the least, whereas LaPO4:Ce/Tb NPs exhibited the largest emission and excitation efficiency, because of the proficient energy transfer amid the co-doped absorber Ce3+ and emitter Tb3+ ions. These observed findings are highly beneficial in the development of the most efficient photonic-based material for their multipurpose uses. [ABSTRACT FROM AUTHOR]

The nonlinear properties of zinc germanium diphosphide (ZGP) crystals enable their applications in powerful mid-IR optical parametric oscillators and second-harmonic generators. This paper summarizes the mechanisms of the laser-induced damage (LID) of high-purity ZGP crystals under periodically pulsed nanosecond irradiation by a Ho3+:YAG laser at 2.1 μm. The ZGP samples were manufactured by "LOC" Ent., Tomsk, Russia, or the Harbin Institute of Technology, China. The impact of processing techniques and the post-growing methods for polishing and anti-reflective coatings on the LID threshold are discussed. The importance of the defect structure of the crystal lattice and the parameters of transparent coatings for increasing the LID threshold are also discussed. The impact of the test laser parameters on the LID threshold and the transient area near the LID threshold obtained using digital holography are analyzed. The influence of the pre-damage processes on the optical parametric oscillations is reported. Lastly, the prospects for improving ZGP crystals to further increase the LID threshold are discussed. [ABSTRACT FROM AUTHOR]

In Tb-Dy-Fe alloy systems, Tb0.29Dy0.71Fe1.95 alloy shows giant magnetostrictive properties under low magnetic fields, thus having great potential for transducers, microsensors, and other applications. The C15 cubic crystal structure of Tb-Dy-Fe has long been thought to be the source of giant magnetostriction. It is surprising that such a highly symmetrical crystal structure exhibits such a large magnetostrictive strain. In this work, the lattice parameters of Tb0.29Dy0.71Fe1.95 magnetostrictive materials were studied by processing atomic-resolution images. The selected area diffraction patterns show a face-centered cubic structure, but the fast Fourier transform diagram shows that the cubic structure has obvious distortion. The lattice parameters obtained by geometric phase analysis (GPA) and Gaussian model-based fitting and calculation show that the lattice constants a, b, and c are not strictly equal, and small disturbance of the lattice constants occurs based on the cubic structure. The actual crystal structure of the Tb-Dy-Fe material is a slightly disturbed cubic structure. This variation in the crystal lattice is mainly caused by the inhomogeneous composition and may be related to the giant magnetostrictive properties of Tb-Dy-Fe alloy. [ABSTRACT FROM AUTHOR]

The microstructures of selected F-, Cl-, and OH-bearing martian apatite grains, two in Northwest Africa (NWA) 998 (cumulus apatites, embedded in pyroxene) and a set of four in Nakhla (intercumulus apatites), were studied by focused ion beam–transmission electron microscopy (FIB-TEM) techniques. Our results show that the nanostructure of martian apatite is characterized by a domain structure at the 5–10 nm scale defined by undulous lattice fringes and slight differences in contrast, indicative of localized elastic strain within the lattices and misorientations in the crystal. The domain structure records a primary post-magmatic signature formed during initial subsolidus cooling (T <800 °C), in which halogens clustered by phase separation (exsolution), but overall preserved continuity in the crystalline structure. Northwest Africa 998 apatites, with average Cl/F ratios of 1.26 and 2.11, show higher undulosity of the lattice fringes and more differences in contrast than Nakhla apatites (average Cl/F = 4.23), suggesting that when Cl/F is close to 1, there is more strain in the structure. Vacancies likely played a key role stabilizing these ternary apatites that otherwise would be immiscible. Apatites in Nakhla show larger variations in halogen and rare-earth element (REE) contents within and between grains that are only a few micrometers apart, consistent with growth under disequilibrium conditions and crystallization in open systems. Nakhla apatite preserves chemical zonation, where F, REEs, Si, and Fe are higher in the core and Cl increases toward the outer layers of the crystal. There is no evidence of subsolidus ionic diffusion or post-magmatic fluid interactions that affected bulk apatite compositions in NWA 998 or Nakhla. The observed zonation is consistent with crystallization from a late-stage melt that became Cl-enriched, and assimilation of volatile-rich crustal sediments is the most plausible mechanism for the observed zonation. This work has broader implications for interpreting the chemistry of apatite in other planetary systems. [ABSTRACT FROM AUTHOR]

This is the first study ever to show the impact of high-energy 160 MeV xenon ion irradiation on the properties of 100Cr6 bearing steel. The projected range (Rp) of xenon ions is 8.2 µm. Fluence-dependent variations in the coefficient of friction and wear of the 100Cr6 steel material have been observed. These changes correlate with shifts in the crystal lattice constant and variations in the oxygen, carbon, and iron content in the wear track. Fluence-dependent changes in these parameters have been observed for the first time. Irradiation reduces stresses in the crystal lattice, leading to crystallite size increase. The modifications in the properties of 100Cr6 steel result from radiation-induced defects caused by electronic ion stopping. The degree of these modifications depends on the applied irradiation fluence. Furthermore, the use of a higher irradiation fluence value appears to mitigate the effects produced by a lower fluence. [ABSTRACT FROM AUTHOR]

The phase‐field crystal model allows the study of materials on atomic length and diffusive time scales. It accounts for elastic and plastic deformation in crystal lattices, including several processes such as growth, dislocation dynamics, and microstructure evolution. The amplitude expansion of the phase‐field crystal model (APFC) describes the atomic density by a small set of Fourier modes with slowly‐varying amplitudes characterizing lattice deformations. This approach allows for tackling large, three‐dimensional systems. However, it has been used mostly for modeling basic lattice symmetries. In this work, we present a coarse‐grained description of the hexagonal closed‐packed (HCP) lattice that supports lattice deformation and defects. It builds on recent developments of the APFC model and introduces specific modeling aspects for this crystal structure. After illustrating the general modeling framework, we show that the proposed approach allows for simulating relatively large three‐dimensional HCP systems hosting complex defect networks. [ABSTRACT FROM AUTHOR]

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We report the topochemical syntheses of three polyarylopeptides, wherein triazolylphenyl group is integrated into the backbone of peptide chains. We synthesized three different monomers having azide and arylacetylene as end‐groups from glycine, L‐alanine and L‐valine. We crystallized these monomers and the crystal structures of two of them were determined by single‐crystal X‐ray diffractometry. Due to the steric constraints, both of these monomers crystallized with two molecules, viz. conformers A and B, in the asymmetric unit. Consistently, in both cases, the A‐conformers are antiparallelly π‐stacked and B‐conformers are parallelly slip‐stacked, exploiting weak interactions. Though the arrangements of molecules in the pristine crystals were unsuitable for topochemical reaction, upon heating, they undergo large motion inside the crystal lattice to reach a transient reactive orientation and thereby the self‐sorted conformer stacks react to give a blend of triazole‐linked polyarylopeptides having two different linkages. Due to the large molecular motion inside crystals, the product phase loses its crystallinity. [ABSTRACT FROM AUTHOR]

A model of the arrangement of atoms of interstitial impurity in iron austenite is developed, according to which an introduction of an interstitial impurity atom causes transformation of a regular close packing (CP or FCC) composed of octahedrons and tetrahedrons into a cementite-type local prismatic packing by diagonal flipping. Carbon dissolves in the crystalline structure of iron austenite as a centered five-atom tetrahedral cluster, which represents a fragment of the carbon packing in the crystalline structure of diamond. The diffusion of the impurity atom is accompanied by a transformation into a prism in the neighboring lattice period, while the prismatic packing in the initial location of the impurity atom is reconstructed back into a conventional interstitial void. To check the adequacy of the proposed model, theoretical calculations of the activation enthalpy of carbon and nitrogen diffusion in austenite were performed, according to which the activation enthalpy values are 149 ± 20 and 155 ± 20 kJ/mol, respectively, which is fairly consistent with the experimental data reported in the literature (153 and 169 kJ/mol). [ABSTRACT FROM AUTHOR]