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 Найдено в других БД:Каталог книг и брошюр библиотеки ИФ СО РАН (1)
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1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ruseikina A. V., Solovyov L. A., Chernyshev V. А., Aleksandrovsky A. S., Andreev O. V., Krylova S. N., Krylov A. S., Velikanov D. A., Molokeev M. S., Maximov N. G., Grigoriev M. V., Garmonov A. A., Matigorov A. V.
Заглавие : Synthesis, structure, and properties of EuErCuS3
Место публикации : J. Alloys Compd. - 2019. - Vol. 805. - P.779-788. - ISSN 09258388 (ISSN), DOI 10.1016/j.jallcom.2019.07.059
Примечания : Cited References: 54. - The work was supported by the State budget allocated to the fundamental research in the Ministry of Science and Education, Russian Federation of (Project No. V.45.3.3); by RFBR Grant 17-02-00754 ; by the Ministry of Science and Higher Education of the Russian Federation under Project No 3.9534.2017/8.9.
Аннотация: The crystal structure of the first-synthesized compound EuErCuS3 was determined from X-ray powder diffraction data: orthorhombic crystal system, space group Pnma, structural type Eu2CuS3: a = 10.1005(2) Å, b = 3.91255(4)Å, c = 12.8480(2) Å; V = 507.737(14) Å3, Z = 4, and ρx = 6.266 g/cm3. The temperatures and enthalpies of reversible polymorphic transitions and incongruent melting of the compound were determined by DSC: Tα↔β = 1524 K, ΔНα↔β = 2.3 ± 0.2 kJ∙mol−1; Tβ↔γ = 1575 K, ΔНβ↔γ = 0.7 ± 0.1 kJ∙mol−1; Tγ↔δ = 1602 K; ΔНγ↔δ = 1.3 ± 0.1 kJ∙mol−1 and Tcr = 1735 ± 10 K, ΔНcr = −3.5 ± 0.3 kJ∙mol−1. IR spectra were recorded in the range from 50 to 400 cm−1. The compound was found to be IR-transparent in the range 4000–400 cm−1. The compound was characterized by Raman spectroscopy. The observed spectra featured both Raman lines and luminescence. Ab initio calculations of the EuErCuS3 crystal structure and phonon spectrum were performed, the frequencies and types of fundamental modes were determined, and the involvement of constituent ions in the IR and Raman modes was assessed from an analysis of the ab initio displacement vectors. The vibrational spectra were interpreted. EuErCuS3 manifests a ferrimagnetic transition at 4.8 K. Its microhardness is 2850 MPa. The obtained data can serve as the basis for predicting the properties of EuLnCuS3 compounds. Valence states for Eu (2+) and Er (3+) are proved both by the XRD and optical methods. Optical band gap was found to be 1.934 eV from diffuse reflectance spectrum.
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Denisenko, Yu. G., Sal'nikova E. I., Basova S. A., Molokeev M. S., Krylov A. S., Aleksandrovsky A. S., Oreshonkov A. S., Atuchin V. V., Volkova S. S., Khritokhin N. A., Andreev O. V.
Заглавие : Synthesis of samarium oxysulfate Sm2O2SO4 in the high-temperature oxidation reaction and its structural, thermal and luminescent properties
Коллективы : Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [18-02-00754, 18-32-20011]; Russian Science FoundationRussian Science Foundation (RSF) [19-42-02003]
Место публикации : Molecules. - 2020. - Vol. 25, Is. 6. - Ст.1330. - ISSN 1420-3049(eISSN), DOI 10.3390/molecules25061330
Примечания : Cited References: 56. - This research was funded by the Russian Foundation for Basic Research (Grants 18-02-00754, 18-32-20011) and Russian Science Foundation (project 19-42-02003).
Предметные рубрики: RARE-EARTH SULFATES
SPECTROSCOPIC PROPERTIES
OXYGEN-STORAGE
LN
LA
Аннотация: The oxidation process of samariumoxysulfide was studied in the temperature range of 500–1000 °C. Our DTA investigation allowed for establishing the main thermodynamic (∆Hºexp = −654.6 kJ/mol) and kinetic characteristics of the process (Ea = 244 kJ/mol, A = 2 × 1010). The enthalpy value of samarium oxysulfate (ΔHºf (Sm2O2SO4(monocl)) = −2294.0 kJ/mol) formation was calculated. The calculated process enthalpy value coincides with the value determined in the experiment. It was established that samarium oxysulfate crystallizes in the monoclinic symmetry class and its crystal structure belongs to space group C2/c with unit cell parameters a = 13.7442 (2), b = 4.20178 (4) and c = 8.16711 (8)Å, β = 107.224 (1)°, V = 450.498 (9)Å3, Z = 4. The main elements of the crystalline structure are obtained and the cation coordination environment is analyzed in detail. Vibrational spectroscopy methods confirmed the structural model adequacy. The Sm2O2SO4 luminescence spectra exhibit three main bands easily assignable to the transitions from 4G5/2 state to 6H5/2, 6H7/2, and 6H9/2 multiplets.
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Denisenko Y. G., Sedykh A. E., Molokeev M. S., Oreshonkov A. S., Aleksandrovsky A. S., Krylov A. S., Khritokhin N. A., Sal'nikova E. I., Andreev O. V., Muller-Buschbaum K.
Заглавие : Crystal and electronic structure, thermochemical and photophysical properties of europium-silver sulfate monohydrate AgEu(SO4)2·H2O
Место публикации : J. Solid State Chem. - 2021. - Vol. 294. - Ст.121898. - ISSN 00224596 (ISSN), DOI 10.1016/j.jssc.2020.121898
Примечания : Cited References: 54. - This work was partially supported by the Russian Foundation for Basic Research (Grant 19-33-90258∖19 ). Use of equipment of Krasnoyarsk Regional Center of Research Equipment of Federal Research Center « Krasnoyarsk Science Center SB RAS» is acknowledged
Аннотация: In order to synthesize single crystals of europium-silver double sulfate monohydrate, a hydrothermal reaction route was used. It was found that the crystallization cannot be performed under standard conditions. The compound AgEu(SO4)2·H2O crystallizes in the trigonal crystal system, space group P3221 (a ​= ​6.917(1), c ​= ​12.996(2) Å, V ​= ​538.53(17) Å3). The structure consists of triple-capped trigonal prisms [EuO9], in which one oxygen atom belongs to crystalline water, silver octahedra [AgO6], and sulfate tetrahedra [SO4]. The hydrogen bonds in the system additionally stabilize the structure. The electronic band structure wasstudied by density functional theory calculations which show that AgEu(SO4)2·H2O is an indirect band gap dielectric. Temperature dependent photoluminescence spectroscopy shows emission bands of transitions from the 5D0 state to the spin-orbit components of the 7FJmultiplet (J ​= ​0–6).The ultranarrow transition 5D0 - 7F0 shows a red shift with respect to other europium-containing water-free sulfates that is ascribed to the presence of OH group in the crystal structure in the close vicinity of the Eu3+ ion. An effect of abnormal sensitivity of the Ω4 intensity factor to minor distortions of the local environment is detected for the observed low local symmetry of C2.
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4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ruseikina A. V., Molokeev M. S., Chernyshev V. А., Aleksandrovsky A. S., Krylov A. S., Krylova S. N., Velikanov D. A., Grigoriev M. V., Maximov N. G., Shestakov N. P., Garmonov A. A., Matigorov A. V., Tarasov A. S., Rautskii M. V., Khritokhin N. А., Melnikova L. V., Tretyakov N. Y.
Заглавие : Synthesis, structure, and properties of EuScCuS3 and SrScCuS3
Место публикации : J. Solid State Chem. - 2021. - Vol. 296. - Ст.121926. - ISSN 00224596 (ISSN), DOI 10.1016/j.jssc.2020.121926
Примечания : Cited References: 72. - The work was supported by the Ministry of Science and Higher Education of the Russian Federation under Project No. FEUZ-2020-0054; by RFBR Grant 18-02-00754 ; by the “UMNIK” program research project № 14977GY/2019; by the Ministry of Science and Higher Education of the Russian Federation (contract no. 05.594.21.0019 , unique identification number RFMEFI59420X0019). Maxim S. Molokeev, Anton S. Tarasov and Mikhail V. Rautskii acknowledge additional funding from Research Grant No. 075-15-2019-1886 from the Government of the Russian Federation. The subset research was performed in Research Resource Center “Natural Resource Management and Physico-Chemical Research.” The use of equipment of Krasnoyarsk Regional Center of Research Equipment of Federal Research Center « Krasnoyarsk Science Center SB RAS» is acknowledged
Аннотация: The crystal structures of the first-synthesized compound EuScCuS3 and previously known SrScCuS3 are refined by Rietveld analysis of X-ray powder diffraction data. The structures are found to belong to orthorhombic crystal system, space group Cmcm, structural type KZrCuS3, with a ​= ​3.83413(3) Å, b ​= ​12.8625(1) Å, c ​= ​9.72654(8) Å (SrScCuS3) and a ​= ​3.83066(8) Å, b ​= ​12.7721(3) Å, c ​= ​9.7297(2) Å (EuScCuS3). The temperatures and enthalpies of incongruent melting are the following: Тm ​= ​1524.5 К, ΔHm ​= ​21.6 ​kJ•mol−1 (SrScCuS3), and Тm ​= ​1531.6 К, ΔHm ​= ​26.1 ​kJ•mol−1 (EuScCuS3). Ab initio calculations of the crystal structure and phonon spectrum of the compounds were performed. The types and wavenumbers of fundamental modes were determined and the involvement of ions participating in the IR and Raman modes was assessed. The experimental IR and Raman spectra were interpreted. EuScCuS3 manifests a ferromagnetic transition at 6.4 ​K. The SrScCuS3 compound is diamagnetic. The optical band gaps were found to be 1.63 ​eV (EuScCuS3) and 2.24 ​eV (SrScCuS3) from the diffuse reflectance spectra. The latter value is in good agreement with that calculated by the DFT method. The narrower band gap of EuScCuS3 is explained by the presence of 4f-5d transition in Eu2+ ion that indicates a possibility to control the band gap of the chalcogenides by the inclusion of Eu. The activation energy of crystal structure defects, being the source of additional absorption in the NIR spectral range, was found to be 0.29 ​eV.
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5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ruseikina A. V., Chernyshev V. A., Velikanov D. A., Aleksandrovsky A. S., Shestakov N. P., Molokeev M. S., Grigoriev M. V., Andreev O. V., Garmonov A. A., Matigorov A. V., Melnikova L. V., Kislitsyn A. A., Volkova S. S.
Заглавие : Regularities of the property changes in the compounds EuLnCuS3 (Ln = La-Lu)
Место публикации : J. Alloys Compd. - 2021. - Vol. 874. - Ст.159968. - ISSN 09258388 (ISSN), DOI 10.1016/j.jallcom.2021.159968
Примечания : Cited References: 102. - The work was supported by the Ministry of Science and Higher Education of the Russian Federation under Project No. FEUZ-2020-0054 ; by the " YMNIK " program research project No. 14977GY/2019; by the Ministry of Science and Higher Education of the Russian Federation under project RFMEFI59420X0019
Аннотация: This work contains the results of complex experimental research of the compounds EuLnCuS3 (Ln = La-Lu) enhanced by the DFT calculations. It is aimed at the data replenishment with particular attention to the revelation of regularities in the property changes, in order to extend the potential applicability of the materials of the selected chemical class. The ab initio calculations of the fundamental vibrational modes of the crystal structures were in good agreement with experimental results. The wavenumbers and types of the modes were determined, and the degree of the ion participation in the modes was also estimated. The elastic properties of the compounds were calculated. The compounds were found out to be IR-transparent in the range of 4000–400 cm–1. The estimated microhardness of the compounds is in the range of 2.68–3.60 GPa. According to the DSC data, the reversible polymorphous transitions were manifested in the compounds EuLnCuS3 (Ln = Sm, Gd-Lu): for EuSmCuS3 Tα↔β = 1437 K, ΔНα↔β = 7.0 kJ·mol-1, Tβ↔γ = 1453 K, ΔНβ↔γ = 2.6 kJ·mol-1; for EuTbCuS3 Tα↔β = 1478 K, ΔНα↔β = 1.6 kJ·mol-1, Tβ↔γ = 1516 K, ΔНβ↔γ = 0.9 kJ·mol-1, Tγ↔δ = 1548 K, ΔНγ↔δ = 1.6 kJ·mol-1; for EuTmCuS3 Tα↔β = 1543 K, Tβ↔γ = 1593 K, Tγ↔δ = 1620 K; for EuYbCuS3 Tα↔β = 1513 K, Tβ↔γ = 1564 K, Tγ↔δ = 1594 K; for EuLuCuS3 Tα↔β = 1549 K, Tβ↔γ = 1601 K, Tγ↔δ = 1628 K. In the EuLnCuS3 series, the transition into either ferro- or ferrimagnetic states occurred in the narrow temperature range from 2 to 5 K. The tetrad effect in the changes of incongruent melting temperature and microhardness conditioned on rLn3+ as well as influencing of phenomenon of crystallochemical contraction were observed. For delimiting between space groups Cmcm and Pnma in the compounds ALnCuS3, the use of the tolerance factor t’ = IR(A)·IR(C) + a×IR(B)2 was verified.
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6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Basova S. A., Molokeev M. S., Oreshonkov A. S., Zhernakov M. A., Khritokhin N. A., Aleksandrovsky A. S., Krylov A. S., Sal’nikova E. I., Azarapin N. O., Shelpakova N. A., Muller-Buschbaum K., Denisenko Yu. G.
Заглавие : Thermochemistry, structure, and optical properties of a new β-La2(SO4)3 polymorphic modification
Колич.характеристики :14 с
Место публикации : Inorganics. - 2023. - Vol. 11, Is. 11. - Ст.434. - ISSN 23046740 (eISSN), DOI 10.3390/inorganics11110434
Примечания : Cited References: 58. - The work was partly carried out within the framework of the Strategic Academic Leadership Program “Priority-2030” for the Kazan Federal University and the state assignment of the Kirensky Institute of PhysicsWe acknowledge Lisa-Marie Wagner (JLU Giessen) for help with X-ray powder diffractometry, and Svetlana Volkova and Irina Palamarchuk (UTMN) for help with IR- and UV-spectrometry. The use of equipment provided by the Krasnoyarsk Regional Center of Research Equipment of Federal Research Center “Krasnoyarsk Science Center SB RAS” is acknowledged
Аннотация: A new polymorphic modification of lanthanum sulfate was obtained by thermal dehydration of the respective nonahydrate. According to powder X-ray diffraction, it was established that β-La2(SO4)3 crystallized in the C2/c space group of the monoclinic system with the KTh2(PO4)3 structure type (a = 17.6923(9), b = 6.9102(4), c = 8.3990(5) Å, β = 100.321(3)°, and V = 1010.22(9) Å3). Temperature dependency studies of the unit cell parameters indicated almost zero expansion along the a direction in the temperature range of 300–450 K. Presumably, this occurred due to stretching of the [LaO9]n chains along the c direction, which occurred without a significant alteration in the layer thickness over the a direction. A systematic study of the formation and destruction processes of the lanthanum sulfates under heating was carried out. In particular, the decisive impact of the chemical composition and formation energy of compounds on the thermodynamic and kinetic parameters of the processes was established. DFT calculations showed β-La2(SO4)3 to be a dielectric material with a bandgap of more than 6.4 eV. The processing of β-La2(SO4)3 with the Kubelka–Munk function exhibited low values below 6.4 eV, which indicated a fundamental absorption edge above this energy that was consistent with LDA calculations. The Raman and infrared measurements of β-La2(SO4)3 were in accordance with the calculated spectra, indicating that the obtained crystal parameters represented a reliable structure.
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