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

Главная

Базы данных

Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Каталог книг и брошюр библиотеки ИФ СО РАН

Каталог журналов библиотеки ИФ СО РАН

Труды сотрудников ИФ СО РАН

Область поиска

в найденном

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>S=CRYSTAL-STRUCTURE<.>)

Общее количество найденных документов : 66
Показаны документы с 1 по 20

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Mel'nikova S. V., Molokeev M. S., Laptash N. M., Misyul S. V.
Заглавие : A non-typical sequence of phase transitions in (NH4)3GeF7: optical and structural characterization
Коллективы : RFBR [15-02-02009 a]
Место публикации : Dalton Trans.: Royal Society of Chemistry, 2016. - Vol. 45, Is. 12. - P.5321-5327. - ISSN 1477-9226, DOI 10.1039/c5dt04907e. - ISSN 1477-9234(eISSN)
Примечания : Cited References:25. - The reported study was partially supported by RFBR, research project no. 15-02-02009 a
Предметные рубрики: Crystal-structure
Powder diffraction
NH4F
Fluorination
Аннотация: Single crystals of germanium double salt (NH4)3GeF7 = (NH4)2GeF6·NH4F = (NH4)3[GeF6]F were grown and studied by the methods of polarization optics and X-ray diffraction. The birefringence Δn = (no − ne), the rotation angle of the optical indicatrix ϕ(T) and unit cell parameters were measured in the temperature range 100–400 K. Three structural phase transitions were found at the temperatures: T1↓ = 279.2 K (T1↑ = 279.4 K), T2↑ = 270 K (T2↓ = 268.9 K), T3↓ = 218 K (T3↑ = 227 K). An unusual sequence of symmetry transformations with temperature change was established: P4/mbm (Z = 2) (G1) ↔ Pbam (Z = 4) (G2) ↔ P21/c (Z = 4) (G3) ↔ Pa (Z = 8) (G4). The crystal structures of different phases were determined. The experimental data were additionally interpreted by a group-theoretical analysis of the complete condensate of order parameters taking into account the critical and noncritical atomic displacements. Strengthening of the N–H⋯F hydrogen bonds can be a driving force of the observed phase transitions.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : ZEIN N. E., ZINENKO V. I., FEDOROV A. S.
Заглавие : ABINITIO CALCULATIONS OF PHONON FREQUENCIES AND DIELECTRIC-CONSTANTS IN A(4)B(6) COMPOUNDS
Место публикации : Phys. Lett. A: ELSEVIER SCIENCE BV, 1992. - Vol. 164, Is. 1. - P115-119. - ISSN 0375-9601, DOI 10.1016/0375-9601(92)90916-A
Примечания : Cited References: 20
Предметные рубрики: IV-VI COMPOUNDS
CRYSTAL-STRUCTURE
Аннотация: The transverse and longitudinal optical frequencies at q = 0, the dielectric constant and the effective charges are calculated for the A4B6 type family of the semiconducting compounds GeTe, SnTe and PdTe. The calculations are performed in the framework of the density functional method with the use of the norm-conserving "first-principles" pseudopotentials. The estimated ferroelectric phase transition temperatures and a number of other calculated quantities turned out to be in good agreement with the experimental data. The variations of the electronic structure in the row PbTe-GeTe, which promote the ferroelectric phase transition for GeTe, are discussed.
WOS
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Wang Z. Y., Xia, Zhiguo, Molokeev M. S., Atuchin V. V., Liu Q. L.
Заглавие : Blue-shift of Eu2+ emission in (Ba,Sr)3Lu(PO4)3:Eu2+ eulytite solid-solution phosphors resulting from release of neighbouring-cation-induced stress
Место публикации : Dalton Trans.: Royal Society of Chemistry, 2014. - Vol. 43, Is. 44. - P.16800-16804. - ISSN 1477-9226, DOI 10.1039/c4dt02319f. - ISSN 1477-9234
Примечания : Cited References: 16. - The present work was supported by the National Natural Science Foundations of China (grant no. 51002146, no. 51272242), Natural Science Foundations of Beijing (2132050), the Program for New Century Excellent Talents in the University of the Ministry of Education of China (NCET-12-0950), Beijing Nova Program (Z131103000413047), Beijing Youth Excellent Talent Program (YETP0635) and the Funds of the State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University (KF201306). V.V.A. is partly supported by the Ministry of Education and Science of the Russian Federation.
Предметные рубрики: TUNABLE COLOR TONE
EXCITED WHITE LEDS
CRYSTAL-STRUCTURE
TEMPERATURE
IONS
Аннотация: A series of iso-structural eulytite-type (Ba,Sr)(3)Lu(PO4)(3):Eu2+ solid-solution phosphors with different Sr/Ba ratios were synthesized by a solid-state reaction. Crystal structures of (Ba,Sr)(3)Lu(PO4)(3):Eu2+ were resolved by the Rietveld method, which shows an eulytite-type cubic Bi-4(SiO4)(3) structure with cations disordered in a single C-3 site while the oxygen atoms were distributed over two partially occupied sites. The emission peaks of Ba(3-x)SrxLu(PO4)(3):Eu2+ (0
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Deng, Chenkai, Hao, Shiqiang, Liu, Kunjie, Molokeev M. S., Wolverton, Christopher, Fan, Liubing, Zhou, Guojun, Chen, D.a., Zhao, Jing, Liu, Quanlin
Заглавие : Broadband light emitting zero-dimensional antimony and bismuth-based hybrid halides with diverse structures
Коллективы : Beijing Municipal Natural Science FoundationBeijing Natural Science Foundation [2182080]; National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [51972021, 51702329]; Fundamental Research Funds for the Central UniversitiesFundamental Research Funds for the Central Universities [FRF-IDRY-19-005]; RFBRRussian Foundation for Basic Research (RFBR) [19-52-80003]; Department of Energy, Office of Science Basic Energy SciencesUnited States Department of Energy (DOE) [DE-SC0014520]
Место публикации : J. Mater. Chem. C. - 2021. - Vol. 9, Is. 44. - P.15942-15948. - ISSN 2050-7526, DOI 10.1039/d1tc04198c. - ISSN 2050-7534(eISSN)
Примечания : Cited References: 52. - This work was supported by Beijing Municipal Natural Science Foundation (2182080) and the National Natural Science Foundation of China (51972021 and 51702329). The work was partly supported by the Fundamental Research Funds for the Central Universities (FRF-IDRY-19-005) and by the RFBR according to the research project No. 19-52-80003. S. H. and C. W. (DFT calculations) acknowledge support from the Department of Energy, Office of Science Basic Energy Sciences under Grant DE-SC0014520. Access to QUEST, the supercomputing resources facilities at Northwestern University, is also acknowledged
Предметные рубрики: CRYSTAL-STRUCTURE
LONE-PAIR
EMISSION
PEROVSKITES
TIN
LUMINESCENCE
Аннотация: Low-dimensional organic–inorganic metal halides have recently attracted extensive attention because of their various structures and distinguished photoelectric properties. Herein, we report a series of new zero-dimensional organic–inorganic hybrid metal halides: (TMEDA)3Bi2Cl12·H2O, (TMEDA)3Bi2Br12·H2O, (TMEDA)3Sb2Br12·H2O, and (TMEDA)5Sb6Cl28·2H2O [TMEDA = N,N,N′·trimethylethylenediamine]. (TMEDA)3M2X12·H2O (M = Bi or Sb, X = Cl or Br) crystallizes in the monoclinic space group P21/n, and (TMEDA)5Sb6Cl28·2H2O crystallizes in the orthorhombic space group Pnma. (TMEDA)3M2X12 possesses a zero-dimensional structure with the metal halide ions of [MBr6]3− isolated by the organic TMEDA2+ cations. Interestingly, the (TMEDA)5Sb6Cl28·2H2O structure consists of a combination of corner-connected octahedra [Sb4Cl18]6− and edge-shared [Sb2Cl10]4−, which is quite rare. The light emission of all these compounds was measured, and (TMEDA)3Sb2Br12·H2O exhibits the most intense luminescence. Upon 400 nm ultraviolet light excitation, (TMEDA)3Sb2Br12·H2O exhibited strong broadband yellow emission centered at 625 nm with a full-width at half-maximum of ∼150 nm originating from self-trapped excitons. This work suggests the possibility of new types of hybrid halides by introducing different metal centers and probing the structural evolution and photoluminescent properties, serving as a reference for the relationship between structure and luminescent performance and demonstrating their potential use as phosphors in light-emitting diodes.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Xia Y. F., Liu Y. G., Huang Z. H., Fang M. H., Molokeev M. S., Mei L. F.
Заглавие : Ca6La4(SiO4)2(PO4)4O2:Eu2+: a novel apatite green-emitting phosphor for near-ultraviolet excited w-LEDs
Место публикации : J. Mater. Chem. C: Royal Society of Chemistry, 2016. - Vol. 4, Is. 21. - P.4675-4683. - ISSN 2050-7526, DOI 10.1039/c6tc01418f. - ISSN 2050-7534(eISSN)
Примечания : Cited References:37. - This study was sponsored by the National Natural Science Foundation of China (Grant No. 51472223), the Program for New Century Excellent Talents in University of Ministry of Education of China (Grant No. NCET-12-0951) and the Fundamental Research Funds for the Central Universities (Grant No. 2652015020 and Grant No. 2652015008).
Предметные рубрики: SOLID-SOLUTION PHOSPHORS
PULSED-LASER DEPOSITION
HIGH THERMAL-STABILITY
WHITE-LIGHT
LUMINESCENCE PROPERTIES
ENERGY-TRANSFER
SINGLE-PHASE
CRYSTAL-STRUCTURE
RED LUMINESCENCE
EPITAXIAL-GROWTH
Аннотация: A novel apatite phosphor Ca6La4(SiO4)2(PO4)4O2:Eu2+ was prepared by conventional high-temperature solid-state reaction. Phase purity was examined by XRD and XPS analysis. The crystal structure information, such as space group, cell parameters and atomic coordinates, were refined by the Rietveld method, revealing that Eu2+ occupied the sites of Ca2+ ions. Moreover, low-temperature experiments, including low-temperature PL spectra and low-temperature decay curve, were used to prove the existence of two luminescence centers in Ca6La4(SiO4)2(PO4)4O2:Eu2+. With the increase in doping concentration of Eu2+, the emission wavelength shows a red shift from 498 nm to 510 nm, which is mainly caused by the increase in crystal-field splitting by Eu2+. The optimized concentration of Eu2+ was confirmed to be 0.01, the Rc was calculated to be 20.09 Å and the energy transfer between Eu2+ was demonstrated to be by exchange interaction. Moreover, good thermal stability has been proved by a temperature-dependence experiment; it shows that the phosphor can maintain 55% of emitting intensity at 150 °C compared to that at room temperature. Finally, the Ca6La4(SiO4)2(PO4)4O2:Eu2+ phosphor was fabricated with commercial red (CaAlSiN3:Eu2+) and blue (BAM:Eu2+) phosphor coating on a n-UV chip. This proves that this green phosphor has the potential to be used in a w-LED lamp.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ji H. P., Huang Z. H., Xia, Zhiguo, Molokeev M. S., Atuchin V. V., Huang S. F.
Заглавие : Cation substitution dependent bimodal photoluminescence in whitlockite structural Ca3-xSrx(PO4)2:Eu2+ (0 ≤ x ≤ 2) solid solution phosphors
Место публикации : Inorg. Chem.: American Chemical Society, 2014. - Vol. 53, Is. 20. - P.11119-11124. - ISSN 0020-1669, DOI 10.1021/ic501679f. - ISSN 1520-510X
Примечания : Cited References: 37. - This work was supported by the National Natural Science Foundations of China (Grant Nos. 51032007, 51002146, 51272242), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20130022110006), the Natural Science Foundations of Beijing (2132050), the Program for New Century Excellent Talents in University of Ministry of Education of China (NCET-12-0950), Beijing Nova Program (Z131103000413047), and Beijing Youth Excellent Talent Program (YETP0635). V.V.A. acknowledges the Ministry of Education and Science of the Russian Federation for financial support.
Предметные рубрики: LIGHT-EMITTING-DIODES
EFFICIENT ENERGY-TRANSFER
EMISSION-TUNABLE PHOSPHOR
EXCITED WHITE LEDS
CRYSTAL-STRUCTURE
LUMINESCENCE PROPERTIES
Mn2+ PHOSPHOR
COLOR TONE
PHASE
Eu2+
Аннотация: Cation substitution dependent tunable bimodal photoluminescence behavior was observed in the Ca3-xSrx(PO4)2:Eu2+ (0 ≤ x ≤ 2) solid solution phosphors. The Rietveld refinements verified the phase purity and whitlockite type crystal structure of the solid solutions. The tunable photoluminescence evolution was studied as a function of strontium content, over the composition range 0.1 ≤ x ≤ 2. In addition to the emission band peak at 416 nm in Ca3(PO4)2:Eu2+, the substitution of Ca2+ by Sr2+ induced the emerging broad-band peak at 493-532 nm. A dramatic red shift of the emission peak located in the green-yellow region was observed on an increase of x in the samples with 0.75 ≤ x ≤ 2.00. The two emission bands could be related to the EuOn-Ca9 and EuOn-Ca9-xSrx emitting blocks, respectively. The values for the two kinds of emitting blocks in the solid solutions can be fitted well with the observed intensity evolution of the two emission peaks.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Antonova A. B., Chudin O. S., Vasiliev A. D., Rubaylo A. I., Verpekin V. V., Sokolenko W. A., Pavlenko N. I., Semeikin O. V.
Заглавие : Chemistry of vinylidene complexes. XX. Intramolecular carbonylation of vinylidene on the MnFe center: Spectroscopic and structural study. X-ray structure of the new trimethylenemethane type MnFe complex
Место публикации : J. Organomet. Chem.: Elsevier, 2011. - Vol. 696, Is. 4. - P.963-970. - ISSN 0022-328X, DOI 10.1016/j.jorganchem.2010.10.035
Примечания : Cited References: 52. - This work was partially supported by the Presidium of the Russian Academy of Sciences (Program for Basic Research, Project No. 7.18) and Russian Foundation for Basic Research (Grant No. 09-03-90745-mob_st). Authors are grateful to Prof. N.A. Ustynyuk for useful discussions, Dr. E.A. Shor and Dr. A.M. Shor for giving the data of quantum chemical study.
Предметные рубрики: MOLECULAR-STRUCTURE
ORGANOMETALLIC CHEMISTRY
TRICARBONYL COMPLEXES
UNSATURATED CARBENES
METAL VINYLIDENES
TRANSITION-METALS
ORGANIC-SYNTHESIS
CRYSTAL-STRUCTURE
IRON TRICARBONYL
MANGANESE
Ключевые слова (''Своб.индексиров.''): manganese--iron--carbonyl complexes--heteronuclear vinylidene complexes--intramolecular vinylidene carbonylation--trimethylenemethane complexes
Аннотация: Reactions of Fe-2(CO)(9) with Cp(CO)(2)Mn=C=CHPh (1) and Cp(CO)(PPh3)Mn=C=CHPh (3) gave the heterometallic trimethylenemethane complexes eta(4)-{C[Mn(CO)(2)Cp](CO)CHPh}Fe(CO)(3) (2) and eta(4)-{C[Mn(CO)(PPh3)Cp](CO)CHPh}Fe(CO)(3) (4), respectively. The formation of the benzylideneketene [PhHC=C=C=O] fragment included in complexes 2 and 4 occurs via intramolecular coupling of the carbonyl and vinylidene ligands. The structures of 3 and 4 were determined by single crystal XRD methods. The influence of the nature of the L ligands at the Mn atom on the structural and spectroscopic characteristics of eta(4)-{C[Mn(CO)(L)Cp](CO)CHPh}Fe(CO)(3) (L = CO (2), PPh3 (4)) is considered. According to the VT H-1 and C-13 NMR spectra, complex 2 reversibly transforms in solution into mu-eta(1):eta(1)-vinylidene isomer Cp(CO)(2)MnFe(mu-C=CHPh)(CO)(4) (2a), whereas complex 4 containing the PPh3 ligand is not able to a similar transformation. (C) 2010 Elsevier B.V. All rights reserved.
Смотреть статью, ,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G., Antipina L. Yu., Tomilin F. N., Kuzubov A. A.
Заглавие : Effect of electron correlations on the structure of photoprotein substrates
Коллективы :
Место публикации : JETP Letters. - 2010. - Vol. 91, Is. 9. - P.490-493. - ISSN 0021-3640, DOI 10.1134/S0021364010090122
Примечания : Cited References: 14. - This work was supported by the Russian Foundation for Basic Research (project no. 07-04-00930-a), by the Presidium of the Russian Academy of Sciences (program "Molecular and Cellular Biology"), and by the Siberian Branch, Russian Academy of Sciences (project no. 2).
Предметные рубрики: ANGSTROM RESOLUTION
CRYSTAL-STRUCTURE
AEQUORIN
ENERGY
OBELIN
GAS
Аннотация: The electronic structure and total energy of various isomeric forms of coelenterazine and coelenteramide have been calculated by quantum chemistry methods both in the single-electron approximation and taking into account correlation effects. It has been shown that the inclusion of electron correlations makes it possible to obtain the structure of the coelenteramide close to the experimentally determined structure, as well as to choose the structure of the coelenterazine CLZ(1H) as the most probable isomeric form.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Dudnikov V. A., Orlov Yu. S., Gavrilkin S. Yu., Gorev M. V., Vereshchagin S. N., Solovyov L. A., Perov N. S., Ovchinnikov S. G.
Заглавие : Effect of Gd and Sr ordering in a sites of doped Gd0.2Sr0.8CoO3-δ perovskite on its structural, magnetic, and thermodynamic properties
Место публикации : J. Phys. Chem. C: American Chemical Society, 2016. - Vol. 120, Is. 25. - P,13443-13449. - ISSN 19327447 (ISSN), DOI 10.1021/acs.jpcc.6b04810
Примечания : Cited References: 45. - The authors are thankful to the Russian Science Foundation (Project No. 16-13-00060) for financial support. The magnetic measurements were carried out in the Shared Facility Centre of P. N. Lebedev Physical Institute of RAS.
Предметные рубрики: Ln1-xSrxCoO(3-δ) Ln
PROFILE REFINEMENT
CRYSTAL-STRUCTURE
OXYGEN-CONTENT
COBALTITES
OXIDE
La1-xSrxCoO3-δ
Dy3+
SPIN
Ho3+
Аннотация: Magnetic and thermodynamic properties of perovskite Gd0.2Sr0.8CoO3−δ, with ordered and disordered states of Gd and Sr in the A-sites of the crystal lattice have been studied revealing remarkable differences in the physical properties of the ordered and disordered states. The ordered samples have larger oxygen nonstoichiometry, heat capacity, and thermal expansion anomalies, and abnormal temperature dependence of the magnetization around 350 K.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Knyazev Yu. V., Kazak N. V., Zhandun V. S., Bartolome J., Arauzo A., Belskaya N. A., Bayukov O. A., Bezmaternykh L. N., Ovchinnikov S. G.
Заглавие : Electronic and magnetic states of Fe ions in Co2FeBO5
Коллективы : Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [20-02-00559, 21-52-12033]; Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science [19-42-240016]; President Council on Grants [MK-2339.2020.2]; Spanish Ministry of Economy, Industry and Competitiveness (MINECO) [MAT2017-83468-R]; regional Government of Aragon (RASMIA project) [E12-20R]
Место публикации : Dalton Trans. - 2021. - Vol. 50, Is. 28. - P.9735-9745. - ISSN 1477-9226, DOI 10.1039/d1dt00125f. - ISSN 1477-9234(eISSN)
Примечания : Cited References: 41. - The authors acknowledge Prof. I. S. Lyubutin for helpful discussions and a critical reading of the manuscript. This research is funded by the Russian Foundation for Basic Research (project no. 20-02-00559 and 21-52-12033), the Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science (project no. 19-42-240016) and the President Council on Grants (project no. MK-2339.2020.2). The authors acknowledge financial support from the Spanish Ministry of Economy, Industry and Competitiveness (MINECO Grant No. MAT2017-83468-R and from the regional Government of Aragon (E12-20R RASMIA project)
Предметные рубрики: TOTAL-ENERGY CALCULATIONS
CRYSTAL-STRUCTURE
SINGLE-CRYSTALS
Аннотация: The ludwigite Co2FeBO5 has been studied experimentally using 57Fe Mössbauer spectroscopy and theoretically using DFT + GGA calculations. The room-temperature Mössbauer spectra are composed of four quadrupole doublets corresponding to the high-spin Fe3+ ions in octahedral oxygen coordination. All components undergo splitting below 117 K due to the magnetic hyperfine fields. The DFT + GGA calculations performed for three models of Fe ion distributions have revealed that the ground state corresponds to the “Fe4(HS)” model with the high-spin Fe3+ ions located at the M4 site and the high-spin Co2+ ions located at the M1, M2, and M3 sites. A ferrimagnetic ground state, with the Co and Fe magnetic moments being nearly parallel to the b-axis and a total magnetic moment of circa 1.1μB f.u.−1, was found. The other Fe distributions cause an increase in the local octahedral distortions and transformation of the spin state. The calculated quadrupole splitting values are in good agreement with the experimental values obtained by Mössbauer spectroscopy.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Atuchin V. V., Khyzhun O. Y., Chimitova O. D., Molokeev M. S., Gavrilova T. A., Bazarov B. G., Bazarova J. G.
Заглавие : Electronic structure of β-RbNd(MoO4)2 by XPS and XES
Коллективы : Ministry of Education and Science of the Russian Federation; RFBR [12-02-90806-mol_rf_nr]
Место публикации : J. Phys. Chem. Solids. - 2015. - Vol. 77. - P.101-108. - ISSN 0022-3697, DOI 10.1016/j.jpcs.2014.09.012
Примечания : Cited References: 52. - This study was partially supported by the Ministry of Education and Science of the Russian Federation and RFBR Grant 12-02-90806-mol_rf_nr.
Предметные рубрики: RAY-EMISSION-SPECTROSCOPY
CRYSTAL-STRUCTURE
PHOTOELECTRON-SPECTROSCOPY
LUMINESCENCE PROPERTIES
VIBRATIONAL PROPERTIES
PHOTOEMISSION SPECTRA
OPTICAL-PROPERTIES
TERNARY MOLYBDATE
AB-INITIO
SYSTEM
Ключевые слова (''Своб.индексиров.''): inorganic compounds--chemical synthesis--photoelectron spectroscopy--x-ray diffraction--electronic structure
Аннотация: β-RbNd(MoO4)2 microplates have been prepared by the multistage solid state synthesis method. The phase composition and micromorphology of the final product have been evaluated by XRD and SEM methods. The electronic structure of β-RbNd(MoO4)2 molybdate has been studied employing the X-ray photoelectron spectroscopy (XPS) and X-ray emission spectroscopy (XES). For the molybdate, the XPS core-level and valence-band spectra, as well as XES bands representing energy distribution of the Mo 4d- and O 2p-like states, have been measured. It has been established that the O 2p-like states contribute mainly to the upper portion of the valence band with also significant contributions throughout the whole valence-band region. The Mo 4d-like states contribute mainly to a lower valence band portion
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Atuchin V. V., Aleksandrovsky A. S., Chimitova O. D., Diao C. P., Gavrilova T. A., Kesler V. G., Molokeev M. S., Krylov A. S., Bazarov B. G., Bazarova J. G., Lin Z. S.
Заглавие : Electronic structure of β-RbSm(MoO4)2 and chemical bonding in molybdates
Коллективы : Ministry of Education and Science of the Russian Federation; National Natural Science Foundation of China [11174297, 11474292]; National Basic Research Project of China [2011CB922204]; Foundation of the Director of Technical Institute of Physics and Chemistry, CAS; RAS [24-29]; RFBR [13-02-00825]
Разночтения заглавия :. в WoS: Electronic structure of beta-RbSm(MoO4)2 and chemical bonding in molybdates
Место публикации : Dalton Trans.: Royal Society of Chemistry, 2015. - Vol. 44, Is. 4. - P.1805-1815. - ISSN 1477-9226, DOI 10.1039/c4dt03203a. - ISSN 1477-9234
Примечания : Cited References: 121. - VVA and ASA gratefully acknowledge the Ministry of Education and Science of the Russian Federation for financial support. ZL acknowledges the support by National Natural Science Foundation of China (11174297 and 11474292), the National Basic Research Project of China (2011CB922204), and Foundation of the Director of Technical Institute of Physics and Chemistry, CAS. The work was partially supported by RAS Project 24-29 and RFBR Grant 13-02-00825.
Предметные рубрики: RAY PHOTOELECTRON-SPECTROSCOPY
CRYSTAL-STRUCTURE
X-RAY
NEUTRON-DIFFRACTION
MAGNETIC-PROPERTIES
PHASE-FORMATION
CORE LEVELS
2ND-HARMONIC GENERATION
LUMINESCENCE PROPERTIES
VIBRATIONAL PROPERTIES
Аннотация: Microcrystals of orthorhombic rubidium samarium molybdate, beta-RbSm(MoO4)(2), have been fabricated by solid state synthesis at T = 450 degrees C, 70 h, and at T = 600 degrees C, 150 h. The crystal structure has been refined by the Rietveld method in space group Pbcn with cell parameters a = 5.0984(2), b = 18.9742(6) and c = 8.0449(3) angstrom (R-B = 1.72%). Thermal properties of beta-RbSm(MoO4)(2) were traced by DSC over the temperature range of T = 20-965 degrees C, and the earlier reported β ↔ α phase transition at T similar to 860-910 degrees C was not verified. The electronic structure of beta-RbSm(MoO4) 2 was studied by employing theoretical calculations and X-ray photoelectron spectroscopy. It has been established that the O 2p-like states contribute mainly to the upper part of the valence band and occupy the valence band maximum, whereas the Mo 4d-like states contribute mainly to the lower part of the valence band. Chemical bonding effects have been analysed from the element core level binding energy data. In addition, it was found that the luminescence spectrum of beta-RbSm(MoO4)(2) is rather peculiar among the Sm3+ containing materials. The optical refractive index dispersion in beta-RbSm(MoO4)(2) was also predicted by the first-principles calculations.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Flerov I. N., Gorev M. V.
Заглавие : Entropy and the mechanism of phase transitions in elpasolites
Место публикации : Phys. Solid State: AMER INST PHYSICS, 2001. - Vol. 43, Is. 1. - P127-136. - ISSN 1063-7834, DOI 10.1134/1.1340198
Примечания : Cited References: 33
Предметные рубрики: ORDERED PEROVSKITE PB2MGTEO6
ELASTIC NEUTRON-DIFFRACTION
THERMODYNAMIC PROPERTIES
CUBIC PEROVSKITES
CRYSTAL-STRUCTURE
HIGH-RESOLUTION
PB2MGWO6
CSPBCL3
Аннотация: The phase transitions in series of crystals with the general formulas A(2)BB'X-6 (X = F, Cl, Br, or CN) and Pb2BB'O-6 that belong to the elpasolite family (space group Fm(3) over bar m) are analyzed. The influence of the size and the shape of cations and anions on the entropy and the mechanism of structural distortions is discussed. (C) 2001 MAIK "Nauka/Interperiodica".
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Reshak, Ali H., Alahmed Z. A., Bila J., Atuchin V. V., Bazarov B. G., Chimitova O. D., Molokeev M. S., Prosvirin, Igor P., Yelisseyev, Alexander P.
Заглавие : Exploration of the electronic structure of monoclinic α-Eu2(MoO4)3: DFT-based study and X-ray photoelectron spectroscopy
Коллективы : Russian Foundation for Basic Research [15-32-50586, 15-52-53080]; Ministry of Education and Science of the Russian Federation; CENTEM project - ERDF as part of the Ministry of Education, Youth and Sports OP RDI program [CZ.1.05/2.1.00/03.0088]; CENTEM PLUS - Ministry of Education, Youth and Sports [LO1402]
Место публикации : J. Phys. Chem. C: American Chemical Society, 2016. - Vol. 120, Is. 19. - P.10559-10568. - ISSN 1932-7447, DOI 10.1021/acs.jpcc.6b01489
Примечания : Cited References:85. - This work was partly supported by the Russian Foundation for Basic Research (Grants 15-32-50586 and 15-52-53080). V.V.A. gratefully acknowledges the Ministry of Education and Science of the Russian Federation for the financial support. A.H.R. would like to acknowledge the CENTEM project, reg. no. CZ.1.05/2.1.00/03.0088, cofunded by the ERDF as part of the Ministry of Education, Youth and Sports OP RDI program and, in the follow-up sustainability stage, supported through CENTEM PLUS (LO1402) by financial means from the Ministry of Education, Youth and Sports under the "National Sustainability Programme I". Computational resources were provided by MetaCentrum (LM2010005) and CERIT-SC (CZ.1.05/3.2.00/08.0144) infrastructures.
Предметные рубрики: Density-functional theory
Solid-solution phosphors
Luminescence properties
Optical-properties
Cleaved surface
Core levels
Vibrational properties
Physical-properties
Crystal-structure
Single-crystals
Аннотация: The powder α-Eu2(MoO4)3 sample was prepared by the solid-state reaction method. The phase purity of the final powder product was verified by X-ray diffraction analysis. The constituent element core levels and valence band are measured by X-ray photoelectron spectroscopy as a function of Ar+ ion (2.5 keV, 7-8 μA/cm2) bombardment time. The formation of Mo5+ and Mo4+ states at high bombardment times was detected. The Eu-O and Mo-O bonding was considered in comparison with other Eu3+- and Mo6+-containing oxides using binding energy difference parameters. The transparency range obtained for the pure α-Eu2(MoO4)3 tablet is λ = 0.41-0.97 μm, as estimated at the transmission level of 5%. The short-wavelength cut edge in α-Eu2(MoO4)3 is governed by the direct allowed optical transitions within the band gap of Eg = 3.74 eV (300 K). The band structure of α-Eu2(MoO4)3 was calculated by ab initio methods and strongly different results were obtained for the spin up/down configurations. The Eu-4f states are located around 2.2 eV and -4.0 eV for spin up (↑) and the structures situated at around 6.5 and 5.5 eV for spin down (↓) configuration. The calculated spin magnetic moments are in excellent relation to the Slater-Pauling rule and within the Eu sphere the magnetic moment of 4f electrons is ∼5.99 μB. © 2016 American Chemical Society.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gorev M. V., Flerov I. N., Tressaud A., Bogdanov E. V., Kartashev A. V., Bayukov O. A., Eremin E. V., Krylov A. S.
Заглавие : Heat capacity and magnetic properties of fluoride CsFe2+Fe3+F6 with defect pyrochlore structure
Место публикации : J. Solid State Chem. - 2016. - Vol. 237. - P.330-335. - ISSN 00224596 (ISSN), DOI 10.1016/j.jssc.2016.02.045
Примечания : Cited References: 19. - This study was partially supported by the Grant NSh-924.2014.2 of the President of the Russian Federation for the Support of Leading Scientific Schools.
Предметные рубрики: Crystal-structure
Mossbauer
CsFe2F6
Spectra
Ключевые слова (''Своб.индексиров.''): pyrochlore structure--phase transition--magnetic properties--thermal properties
Аннотация: Heat capacity, Mossbauer and Raman spectra as well as magnetic properties of fluoride CsFe2F6 with defect pyrochlore structure were studied. In addition to recently found above room temperature three successive structural transformations Pnma-Imma-I41amd-Fd-3m, phase transition of antiferromagnetic nature with the 13.7 K Neel temperature and a broad heat capacity anomaly with a maximum at about 30 K were observed. The room temperature symmetry Pnma is unchanged at least down to 7 K. Simple model of indirect bond used to estimate the exchange interactions and to propose a magnetic structure model. © 2016 Elsevier Inc. All rights reserved.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Flerov I. N., Gorev M. V., Sciau P.
Заглавие : Heat capacity and p-T phase diagrams of the ordered perovskites Pb2MgWO6 and Pb2CoWO6
Место публикации : J. Phys.: Condens. Matter: IOP PUBLISHING LTD, 2000. - Vol. 12, Is. 5. - P.559-567. - ISSN 0953-8984, DOI 10.1088/0953-8984/12/5/304
Примечания : Cited References: 25
Предметные рубрики: CRYSTAL-STRUCTURE
X-RAY
TRANSITIONS
PRESSURE
Аннотация: The heat capacities of Pb2MgWO6 and Pb2CoWO6 and the effect of hydrostatic pressure on the phase transitions have been studied on powdered samples by means of an adiabatic calorimeter and DTA performed under pressure, respectively. Thermodynamic parameters, such as change of total excess entropy, latent hear and hysteresis of the phase transition temperature were determined. Entropies and p-T phase diagrams are discussed in connection with structural data.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gorev M. V., Flerov I. N., Sciau P.
Заглавие : Heat capacity and the p-T phase diagram of Pb2MgTeO6 elpasolite
Место публикации : Phys. Solid State: AMER INST PHYSICS, 2001. - Vol. 43, Is. 2. - P345-349. - ISSN 1063-7834, DOI 10.1134/1.1349486
Примечания : Cited References: 17
Предметные рубрики: ORDERED PEROVSKITE PB2MGTEO6
CRYSTAL-STRUCTURE
PB2COWO6
PB2MGWO6
Аннотация: The heat capacity of Pb2MgTeO6 is measured in the temperature range 80-300 K. It is found that the heat capacity exhibits an anomaly associated with the phase transition at T-0 = 186.9 K. The thermodynamic parameters of the structural transformation are determined. The effect of hydrostatic pressure up to 0.5 GPa on the phase transition temperature is examined. (C) 2001 MAIK "Nauka/Interperiodica".
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pogoreltsev E. I., Flerov I. N., Kartashev A. V., Bogdanov E. V., Laptash N. M.
Заглавие : Heat capacity, entropy, dielectric properties and T–p phase diagram of (NH4)3TiF7
Коллективы : Russian Foundation for Basic Research [15-02-02009]; Council on Grants from the President of the Russian Federation for the Support of Leading Scientific Schools of the Russian Federation [NSh-924.2014.2]
Место публикации : J. Fluor. Chem.: Elsevier Science, 2014. - Vol. 168. - P.247-250. - ISSN 0022-1139, DOI 10.1016/j.jfluchem.2014.10.016. - ISSN 1873-3328
Примечания : Cited References: 16. - This work was supported by the Russian Foundation for Basic Research (Grant no. 15-02-02009), and the Council on Grants from the President of the Russian Federation for the Support of Leading Scientific Schools of the Russian Federation (Grant no. NSh-924.2014.2).
Предметные рубрики: CRYSTAL-STRUCTURE
TRANSITIONS
FLUORIDES
NH4F
Ключевые слова (''Своб.индексиров.''): cubic fluorides--phase transitions--dielectric--phase diagram--calorimetry
Аннотация: Successive phase transitions G1 -- G2 -- G3 in the double salt (NH4)(3)TiF7 have been studied by detailed calorimetric, DTA under hydrostatic pressure and dielectric measurements. Rather large entropy jumps at phase transition points were found to be followed by large additional contributions associated with the temperature dependence of the excess heat capacity. The permittivity behaviour and the tangent of the dielectric losses proved the nonferroelectric nature of both transformations. Two triple-points were found on the temperature-pressure phase diagram, suggesting the existence of a hypothetical parent G0 = Pm-3m cubic phase. A direct transformation between high (G0) and low (G3) temperature cubic phases takes place at p 0.41 GPa with a baric coefficient dT(G0) -- (G3)/dp = -40 K/GPa. (C) 2014 Elsevier B.V. All rights reserved.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Golovnev N. N., Molokeev M. S., Samoilo A. S., Atuchin V. V.
Заглавие : Influence of alkyl substituents in 1,3-diethyl-2-thiobarbituric acid on the coordination environment in M(H2O)2(1,3-diethyl-2-thiobarbiturate)2 M = Ca2+, Sr2+
Место публикации : J. Coord. Chem.: Taylor & Francis, 2016. - Vol. 69, Is. 6. - P.957-965. - ISSN 00958972 (ISSN), DOI 10.1080/00958972.2016.1149168
Примечания : Cited References: 42. - The study was carried out within the public task of the Ministry of Education and Science of the Russian Federation for research engineering of the Siberian Federal University in 2015-2016. V.V.A. is grateful to the Ministry of Education and Science of the Russian Federation for the financial support of the investigation.
Предметные рубрики: CRYSTAL-STRUCTURE
2-THIOBARBITURIC ACID
STRUCTURAL-CHARACTERIZATION
THIOBARBITURIC ACID
THERMAL-PROPERTIES
HYDROGEN-BOND
COMPLEXES
DIFFRACTION
NETWORKS
POLYMERS
Ключевые слова (''Своб.индексиров.''): 1,3-diethyl-2-thiobarbituric acid--alkaline earth metals--coordination compound--x-ray diffraction--thermal analysis
Аннотация: Two new isostructural complexes, [Ca(H2O)2(μ2-Detba-O,O′)2]n (1) and [Sr(H2O)2(μ2-Detba-O,O′)2]n (2) (HDetba = 1,3-diethyl-2-thiobarbituric acid), were synthesized and characterized by single-crystal and powder X-ray diffraction analysis, TG-DSC, FT-IR, and emission spectroscopy. The single-crystal X-ray diffraction data revealed that 1 and 2 are polymeric where M2+ (M = Ca, Sr) is a six-coordinate octahedral binding four Detba− ions and two water molecules. The octahedra are linked through bridging Detba− ions forming a 2-D layer. Two intermolecular hydrogen bonds O–H…S in the crystal form a 3-D net. The comparison of M(Detba)2 and M(Htba)2 (H2tba = 2-thiobarbituric acid) structures showed that the coordination number of metals in M(Detba)2 does not exceed six and there are no π–π interactions, unlike compounds with Htba−; Detba− ions are only bridges in HDetba coordination compounds. Thermal decomposition of 1 and 2 includes dehydration, which mainly ends at 200 °C, and organic ligand oxidation at 300–350 °C with a release of CO2, SO2, H2O, NH3, and isocyanate. Upon excitation at 220 nm, 1 and 2 exhibit an intense emission maximum at 557 nm.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Mel'nikova S. V., Isaenko L. I., Gorev M. V., Vasil'ev A. D., Lobanov S. I.
Заглавие : Investigation of the structure, physical properties, and phase transition in SrAlF5
Коллективы :
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2010. - Vol. 52, Is. 3. - P509-514. - ISSN 1063-7834, DOI 10.1134/S1063783410030108
Примечания : Cited References: 16. - This study was supported by the Russian Foundation for Basic Research (project no. 07-02-00442) and the Siberian Branch of the Russian Academy of Sciences within the framework of the Interdisciplinary Integration Project No. 34.
Предметные рубрики: CRYSTAL-STRUCTURE
BEHAVIOR
GROWTH
SRAIF5
Аннотация: Crystals of SrAlF5 have been grown by the Bridgman method from the melt and by sintering of the components. Optical polarization studies and measurements of the thermal expansion and birefringence coefficients have been carried out over a wide temperature range. The electromechanical coefficient d (33) has been measured, and the optical second harmonic, dielectric hysteresis loop, and optical quality of the crystal have been assessed. X-ray diffraction investigations have been performed to identify the revealed compounds. It has been demonstrated that the SrAlF5 crystals obtained under the growth conditions chosen have I4(1)/a symmetry and do not undergo structural phase transitions in the temperature range 100-800 K. Crystalline inclusions of the AlOF oxyfluoride have been revealed in crystals grown with an AlF3 excess. The birefringence of the AlOF crystal is an order of magnitude higher than that of SrAlF5, does not depend on temperature, and has no anomalies up to 800 K.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие