Библиотека института физики им. Л.В. Киренского СО РАН

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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Grigoriev, Maxim V., Ruseikina, Anna V., Molokeev M. S., Chernyshev, Vladimir А., Aleksandrovsky A. S., Krylov A. S., Krylova S. N., Shestakov N. P., Velikanov D. A., Garmonov, Alexander A., Matigorov, Alexey V., Ostapchuk, Evgeny A., Schleid, Thomas, Safin, Damir A.
Заглавие : Elucidating elusive quaternary selenide EuCeCuSe3: Synthesis, crystal structure, properties and theoretical studies
Колич.характеристики :9 с
Место публикации : J. Rare Earths. - 2024. - Vol. 42, Is. 1. - P.163-171. - ISSN 10020721 (ISSN), DOI 10.1016/j.jre.2022.11.004. - ISSN 25094963 (eISSN)
Примечания : Cited References: 47
Аннотация: We report on the novel heterometallic quaternary selenide EuCeCuSe3, the fabrication of which has been a challenge until this work. The structure of the reported selenide was elucidated from the powder X-ray diffraction data, which revealed the formation of EuCeCuSe3 with excellent yield (96.7%) accompanied with a minor fraction of CeSe2 (3.3%), and was best solved in orthorhombic space group Pnma with the BaLaCuS3 structural type. Thus, the crystal structure of the title compound completes the row of the heterometallic quaternary selenides EuRECuSe3 (RE = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y), of which the cerium-based derivative exclusively belongs to the BaLaCuS3 structural type. The distortion of the CuSe4 polyhedron was compared for the whole series of EuRECuSe3 compounds using the τ4-descriptor for four coordinated ions, which revealed the highest degree of distortion for the Ce3+-containing selenide, followed by the La3+-based derivative. Furthermore, the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3 and EuCeCuS3. Ab initio calculations of the crystal structure, a phonon spectrum and elastic constants for the crystal of EuСeCuSe3 were also performed. The types and wavenumbers of fundamental modes were determined and the involvement of ions participating in the phonon modes was assessed. The experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated spectrum. The experimental direct band gap of EuCeCuSe3 was measured to be 1.36 eV that is consistent with the concept of its origin due to interband transitions between orbitals emerging mainly from 4f (valence band) and 5d (conduction band) levels of the Eu2+ cation. The dependence of the Young's modulus on the direction demonstrates the anisotropy of the elastic properties, while the Vickers hardness for EuCeCuSe3 was calculated to be 5.2 GPa. Finally, the title compound is paramagnetic above 4 K.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zhandun V. S., Draganyuk O. N., Zamkova N. G.
Заглавие : Magnetic structure and pressure-induced spin-crossover in Me3B2O6 (Me = Mn, Fe, Co, Ni) kotoites: Representation analysis and DFT calculations
Колич.характеристики :10 с
Место публикации : Comput. Mater. Sci. - 2024. - Vol. 236. - Ст.112859. - ISSN 09270256 (ISSN), DOI 10.1016/j.commatsci.2024.112859. - ISSN 18790801 (eISSN)
Примечания : Cited References: 25. - The study was funded by a grant from the Russian Science Foundation # 22-22-20024 https://rscf.ru/project/22-22-20024/, Krasnoyarsk Regional Fund of Science. The calculations were performed with the computer resources of “Complex modeling and data processing research installations of mega-class” SRC “Kurchatovsky Institute” (http://ckp.urcki.ru). VZ thanks Dr. Natalia Kazak and Oksana Draganyuk for help in preparing the manuscript, useful discussions and valuable advices
Аннотация: The magnetic and electronic properties of transition metal borates Me3B2O6 (Me = Mn, Fe, Co, Ni) with kotoite structure have been investigated at ambient and high pressures via a combination of representation analysis and density functional theory (DFT + U) calculations. Several magnetic configurations corresponding to the different irreducible representations have been considered. The total-energy calculations reveal that the magnetic ground state of Me3B2O6 kotoites is composition-dependent. The lowest energy magnetic phase of manganese and nickel kotoites is characterized by the antiferromagnetic ordering of the transition metal magnetic moments along the c- axis and along the b-axis for cobalt and iron kotoites. The magnetic cell of Ni3B2O6 kotoite corresponds to k = (1/2, 0, 1/2) vector and four time larger than the unit cell. The calculated exchange constants indicate the competition between ferromagnetic and antiferromagnetic interactions. At a critical pressure, Me ions undergo a high-spin to low-spin state crossover. This magnetic moments collapse is analyzed in terms of change in electronic structure under pressure.
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Вид документа : Статья из журнала
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Автор(ы) : Zhandun V. S., Kazak N. V., Kupenko I., Vasiukov D., Li X., Blackburn E., Ovchinnikov S. G.
Заглавие : Orthogonal magnetic structures of Fe4O5: representation analysis and DFT calculations
Колич.характеристики :10 с
Место публикации : Dalton Trans. - 2024. - Vol. 53, Is. 5. - P.2242-2251. - ISSN 14779226 (ISSN), DOI 10.1039/D3DT03437B. - ISSN 14779234 (eISSN)
Примечания : Cited References: 45. - V.S. Zhandun and N.V. Kazak acknowledge the support provided by the Russian Foundation for Basic Research (project no. 21-52-12033). I. Kupenko acknowledges the support provided by the German Research Foundation (DFG) through the DFG Project AOBJ: 674300 GZ.:KU 3832/3-1. D. Vasiukov acknowledges the support provided by the Swedish Research Council (project no.2018-04704). The calculations were performed with the computer resources of "Complex modeling and data processing research installations of mega-class" SRC "Kurchatovsky Institute” (http://ckp.urcki.ru)We thank Arno Rohrbach and Stephan Klemme (Universität Münster) for their help with the synthesis of the Fe4O5 crystals. The authors acknowledge the European Synchrotron Radiation Facility for provision of synchrotron radiation facilities and we would like to thank G. Aprilis for assistance and support in conducting SMS experiments and in using Nuclear Resonance beamline ID18 and D. Comboni for assistance and support in conducting XRD experiments and using High-Pressure Diffraction Beamline ID15b
Аннотация: The magnetic and electronic structures of Fe4O5 have been investigated at ambient and high pressures via a combination of representation analysis, density functional theory (DFT+U) calculations, and Mossbauer spectroscopy. A few spin configurations corresponding to the different irreducible representations have been considered. The total-energy calculations reveal that the magnetic ground state of Fe4O5 corresponds to an orthogonal spin order. Depending on the magnetic propagation vector k two spin ordered phases with minimal energy differences are realized. The lowest energy magnetic phase is related to k = (0, 0, 0) and is characterized by the ferromagnetic ordering of the iron magnetic moments at prismatic sites along the b axis and antiferromagnetic ordering of iron moments at octahedral sites along the c axis. For the k = (1/2, 0, 0) phase, the moments in the prisms are antiferromagnetically ordered along the b axis and the moments in the octahedra are still antiferromagnetically ordered along the c axis. Under high pressure, the Fe4O5 exhibits magnetic transitions with corresponding electronic transitions of the metal-insulator type. At a critical pressure PC ~ 60 GPa the Fe ions at the octahedral sites undergo a high-spin to low-spin state crossover with a decrease in the unit-cell volume of ~ 4%, while the Fe ions at the prismatic sites remain in the high-spin state up to 130 GPa. This site-dependent magnetic collapse is experimentally observed in the transformation of Mossbauer spectra measured at room temperature and high pressures.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zhandun V. S., Kazak N. V., Vasiukov D. M.
Заглавие : Magnetic structure of Fe5O6: Group-theoretical analysis and DFT calculations
Колич.характеристики :5 с
Место публикации : JETP Lett. - 2024. - Vol. 119, Is. 4. - P.294-298. - ISSN 00213640 (ISSN), DOI 10.1134/S0021364023604244. - ISSN 10906487 (eISSN)
Примечания : Cited References: 27. - V. Zhandun and N. Kazak acknowledge the support of the Russian Science Foundation (project no. 21-52-12033) and D. Vasiukov acknowledges the support of the Swedish Research Council (project no. 2018-04704)
Аннотация: The magnetic structure of Fe5O6 is studied using a combination of the group-theoretical analysis and DFT + U calculations of the electronic spectrum. The calculations are performed for the magnetic k = (0, 0, 0) vector. The magnetic ground state corresponds to the orthogonal ordering of two magnetic subsystems: the magnetic moments of Fe2+/Fe3+ ions located at the octahedral sites (slabs of octahedra) are directed along the c axis and are antiferromagnetically ordered, whereas the magnetic moments of Fe2+ ions in trigonal prisms forming one-dimensional chains are directed along the b axis and are antiferromagnetically coupled along the c axis. The formation of a nonzero antiferromagnetic component of magnetic moments in the slabs of octahedra directed along the b axis is caused by the effect of magnetic chains on the three-dimensional magnetic structure.
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Вид документа : Статья из журнала
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Автор(ы) : Sofronova S. N., Chernyshev A.
Заглавие : Magnetic ordering and the role of superexchange Ni–O–B–O–Ni upon the formation of magnetic order in ludwigite Ni2MnBO5 from first-principal calculations
Место публикации : Comput. Condens. Matter. - 2024. - Vol. 40. - Ст.e00918. - ISSN 23522143 (eISSN), DOI 10.1016/j.cocom.2024.e00918
Примечания : Cited References: 28
Аннотация: The energies of various magnetically ordered structures for ludwigite Ni2MnBO5 have been calculated in the framework of the first-principles approach using the Wien2K program package, with the parameters of exchange interactions being determined. Two subsystems can be distinguished in the magnetic system, which are associated with the triads 4-2-4 and 3-1-3. The magnetic moments of the ions in both triads are antiferromagnetically oriented. The analysis of the exchange contribution to the energy shows that there occurs an increase of the magnetic cell relative to the crystallographic one due to antiferromagnetic ordering of the magnetic moments along the c axis in three-legged ladders formed by 4-2-4 triads. However, in three-legged ladders formed by 3-1-3 triads, the magnetic moments of the ions are ordered along the c-axis ferromagnetically. The predicted type of magnetic ordering in Ni2MnBO5 is similar to magnetic ordering in Fe3BO5. Non-collinear ordering of the magnetic moments of the subsystems at different temperatures is also likely to be observed in Ni2MnBO5, as is the case in Fe3BO5. Superexchange (indirect) interactions (No-O-B-O-Ni) influence the orientation of the magnetic moments of two 3-1-3 (4-2-4) triads within the unit cell. It is these interactions that may be responsible for the formation of long-range magnetic order in Co3BO5 and ferrimagnetic-antiferromagnetic spin-reorientation transition in Fe3BO5.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Chernyshev V. A., Ruseikina A. V., Grigoriev M. V., Krylova S. N., Safin D. A.
Заглавие : First-principles calculations to investigate optical, phonon and electronic properties of quaternary sulfides SrRECuS3 (RE = La, Nd, Tm)
Колич.характеристики :7 с
Место публикации : Inorg. Chem. Commun. - 2024. - Vol. 165. - Ст.112449. - ISSN 13877003 (ISSN), DOI 10.1016/j.inoche.2024.112449. - ISSN 18790259 (eISSN)
Примечания : Cited References: 43. - This work was supported by The Ministry of Science and Higher Education of the Russian Federation (project No. FEUZ-2023-0017)
Аннотация: The structure and properties of three layered heterometallic quaternary sulfides SrLaCuS3, SrNdCuS3 and SrTmCuS3 were studied for the first time using first-principles calculations in the stoichiometric and nonstoichiometric approximations. The applied DFT-based computations were performed using a hybrid functional with the contribution of nonlocal exchange in the Hartree-Fock formalism. It was revealed that the nonstoichiometry of SrLaCuS3 and SrNdCuS3 must be considered for modeling phonon spectra, elastic properties and band gaps. The wavenumbers and types of the Raman and "silent" modes at the Г-point were determined. From the analysis of displacement vectors, the degree of participation of ions in each mode was determined. The elastic constants and elastic moduli of the reported sulfides were calculated.
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Вид документа : Статья из журнала
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Автор(ы) : Zhandun V. S., Zamkova N. G., Draganyuk O. N.
Заглавие : The arising of ferromagnetism in Al-doped Mn2(Ga1−xAlx)C MAX phases
Колич.характеристики :5 с
Место публикации : J. Magn. Magn. Mater. - 2024. - Vol. 601. - Ст.172193. - ISSN 03048853 (ISSN), DOI 10.1016/j.jmmm.2024.172193. - ISSN 18734766 (eISSN)
Примечания : Cited References: 30. - The study was funded by a grant from the Russian Science Foundation # 23-22-10020 https://rscf.ru/project/23-22-10020/, Krasnoyarsk Regional Fund of Science. The calculations were performed with the computer resources of "Complex modeling and data processing research installations of mega-class" SRC "Kurchatovsky Institute" (http://ckp.urcki.ru). The ternary phase diagrams for the calculation of formation enthalpies were taken from Materials Project (https://materialsproject.org) and OQMD (https://oqmd.org/) databases
Аннотация: The magnetic properties of ordered MAX phases Mn2(AlxGa1−x)C (x = 0.125, 0.25, 0.5, 0.75 and 0.875) have been studied within the DFT-GGA. We have found that increase of Al atom at A-site leads to the formation of the ferromagnetic phase with large magnetization of about 3.6 μB/f.u. The investigation of the phase stability is performed by comparing the total energy of the MAX phases with that of a set of competitive phases for calculation of the phase formation enthalpy. Up to a concentration of Al atoms x = 0.7 the compound remains thermodynamically stable. The exchange constants analysis shows the crucial role of exchange interactions between manganese atoms along the c-axis in forming of ferromagnetism. The magnetic transition temperature of Mn2(AlxGa1−x)C alloys increases with increase of the aluminum concentration.
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Вид документа : Статья из журнала
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Автор(ы) : Habibullayev N. N., Naumov N. G., Lavrov A.N., Kuratieva N. V., Aleksandrovsky A. S., Oreshonkov A. S., Molokeev M. S., Palamarchuk I. V., Yurev I. O., Denisenko Y. G., Andreev O. V., Zakharova A. D.
Заглавие : Magnetic, optical, and thermic properties of SrLnCuSe3 (Ln = Dy, Ho, Er, Tm) compounds
Место публикации : Magnetochemistry. - 2023. - Vol. 9, Is. 8. - Ст.194. - ISSN 23127481 (eISSN), DOI 10.3390/magnetochemistry9080194
Примечания : Cited References: 36. - The study was funded by the Russian Science Foundation, project No. 23-23-00488
Аннотация: SrLnCuSe3 (Ln = Dy, Ho, Er, Tm) compounds crystallize in the Pnma and Cmcm orthorhombic space group and belong to the Eu2CuS3 and KCuZrS3 structural type, respectively. According to a single-crystal XRD study, the SrTmCuSe3 unit cell parameters are a = 4.0631 (4), b = 13.4544 (14), c = 10.4430 (10) A, and V = 570.88 (10) A3. All the studied SrLnCuSe3 samples in the temperature range of 1.77–300 K demonstrate paramagnetic behavior without any features pointing to magnetic ordering. The measured Curie constants coincide with the values expected for Ln3+ ions with good accuracy, which confirms the stoichiometric composition of the samples and the non-magnetic state of the copper ions, Cu1+ (S = 0). The conducted optical absorption study showed that the polycrystalline SrLnCuSe3 (Ln = Dy, Ho, Er, Tm) samples are semiconductors with a direct bandgap ranging from 2.14 eV to 2.31 eV. Two indirect bandgaps were revealed and explained by the presence of optical transitions to highly dispersive subbands in the conduction band. The compounds demonstrate two reversible phase transitions α⇆β, β⇆γ and an incongruent melting at 1606 K (Dy), 1584 K (Ho), 1634 K (Er), and 1620 K (Tm) associated with the formation of solid solutions of SrSe, Cu2-XSe, and Ln2Se3 binary compounds.
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Вид документа : Статья из журнала
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Автор(ы) : Oreshonkov A. S., Sukhanova E. V., Popov Z. I.
Заглавие : Phonon dynamics in MoSi2N4: insights from DFT calculations
Колич.характеристики :11 с
Место публикации : Phys. Chem. Chem. Phys. - 2023. - Vol. 25, Is. 43. - P.29831-29841. - ISSN 14639076 (ISSN), DOI 10.1039/D3CP02921B. - ISSN 14639084 (eISSN)
Примечания : Cited References: 74. - The authors acknowledge financial support from Russian Science Foundation (project №21-73-20183, https://rscf.ru/project/21-73-20183/)
Аннотация: We have reported the density functional theory investigations on the monolayer, 2 layered and bulk MoSi2N4 in three structural modifications called as α1 [Science, DOI: 10.1126/science.abb7023], α2 and α3 [Adv. Funct. Mater., DOI: 10.1002/adfm.202214050]. We showed that in the case of monolayers the difference in total energies is less than 0.1 eV between α1 and α3 phases, and less than 0.2 eV between α1 and α2 geometries. The most energetically favorable layer stacking for the bulk structures of each phase was investigated. All considered modifications are dynamically stable from a single layer to a bulk structure in energetically favorable stacking. Raman spectra for the monolayer, 2 layered and bulk structures were simulated and the vibrational analysis was performed. The main difference between in the obtained spectra is associated with the position of the strongest band which depends on the Mo-N bond length. According to the obtained data, we can conclude that Raman line at 348 cm–1 in the experimental spectra of MoSi2N4, can have more complex explanation then just Γ-point Raman-active vibration as was discussed before in [Science, DOI: 10.1126/science.abb7023].
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Grigoriev, Maxim V., Ruseikina, Anna V., Chernyshev, Vladimir A., Oreshonkov A. S., Garmonov, Alexander A., Molokeev M. S., Locke, Ralf J. C., Elyshev, Andrey V., Schleid, Thomas
Заглавие : Single crystals of EuScCuSe3: Synthesis, experimental and DFT investigations
Место публикации : Materials. - 2023. - Vol. 16, Is. 4. - Ст.1555. - ISSN 19961944 (eISSN), DOI 10.3390/ma16041555
Примечания : Cited References: 39. - This research was funded by the Tyumen Oblast Government as part of the West-Siberian Interregional Science and Education Center’s project No. 89-DON (3). The work was supported by The Ministry of Science and Higher Education of the Russian Federation, project, No. FEUZ-2023-0017
Аннотация: EuScCuSe3 was synthesized from the elements for the first time by the method of cesium-iodide flux. The crystal belongs to the orthorhombic system (Cmcm) with the unit cell parameters a = 3.9883(3) Å, b = 13.2776(9) Å, c = 10.1728(7) Å, V = 538.70(7) Å3. Density functional (DFT) methods were used to study the crystal structure stability of EuScCuSe3 in the experimentally obtained Cmcm and the previously proposed Pnma space groups. It was shown that analysis of elastic properties as Raman and infrared spectroscopy are powerless for this particular task. The instability of EuScCuSe3 in space group Pnma space group is shown on the basis of phonon dispersion curve simulation. The EuScCuSe3 can be assigned to indirect wide-band gap semiconductors. It exhibits the properties of a soft ferromagnet at temperatures below 2 K.
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