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=OXIDES<.>)

Общее количество найденных документов : 32
Показаны документы с 1 по 20

1-20 21-32

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Avramov P. V., Ovchinnikov S. G.
Заглавие : Effects of the intense electron correlations on the shape of x-ray CuK absorption spectra of La2-xSrxCuO4
Место публикации : Zhurnal Eksperimentalnoi Teor. Fiz.: MEZHDUNARODNAYA KNIGA, 1995. - Vol. 108, Is. 4. - P.1479-1488. - ISSN 0044-4510
Примечания : Cited References: 28
Предметные рубрики: HIGH-TC SUPERCONDUCTIVITY
EDGE STRUCTURE
LA2CUO4
SATELLITES
ALPHA
EXCITATIONS
COPPER
OXIDES
STATE
SHAKE
WOS
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Avramov P. V., Ovchinnikov S. G.
Заглавие : Non-diagram transitions in polarized X-ray absorption CuL(3) spectra of HTSC-ceramics
Место публикации : Fiz. Tverd. Tela: MEZHDUNARODNAYA KNIGA, 1996. - Vol. 38, Is. 11. - P3226-3240. - ISSN 0367-3294
Примечания : Cited References: 28
Предметные рубрики: HIGH-TC SUPERCONDUCTIVITY
LA2CUO4
ALPHA
SATELLITES
STATES
OXIDES
XANES
WOS
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Beznosikov B. V., Aleksandrov K. S.
Заглавие : Perovskite-like crystals of the Ruddlesden-Popper series
Место публикации : Crystallogr. Rep.: MAIK Nauka-Interperiodica / Springer, 2000. - Vol. 45, Is. 5. - P.792-798. - ISSN 1063-7745, DOI 10.1134/1.1312923
Примечания : Cited References: 28
Предметные рубрики: CUPRATE
OXIDES
Аннотация: The layer perovskite-like structures of the so-called Ruddlesden-Popper phases have been analyzed in terms of crystal chemistry. The geometrical boundaries of the existence ranges of these compounds with multilayer stacks are determined and new phases of this type are predicted. The possible variants of related structures are also considered. (C) 2000 MAIK "Nauka/Interperiodica".
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Borisov A. A., Gavrichkov V. A., Ovchinnikov S. G.
Заглавие : Doping dependence of the band structure and chemical potential in cuprates by the generalized tight-binding method
Коллективы : International Conference on Modern Problems in Superconductivity
Место публикации : Mod. Phys. Lett. B/ International Conference on Modern Problems in Superconductivity (3 ; 2002 ; Sept. ; 9-14 ; Yalta, Ukrain). - 2003. - Vol. 17, Is. 10-12. - P.479-486. - ISSN 0217-9849, DOI 10.1142/S0217984903005500
Примечания : Cited References: 12
Предметные рубрики: CORRELATED ELECTRONS
SUPERCONDUCTIVITY
OXIDES
Аннотация: Quasiparticle band structure in hole doped CuO2 layer is calculated with account for strong electron correlations in the framework of multiband p-d model. For undoped layer we obtain the charge-transfer antiferromagnetic insulator. With doping unusual impurity-like quasiparticle appears at the top of the valence band with spectral weight proportional to doping concentration. In the overdoped regime the band structure in the paramagnetic phase results in the doping dependent Fermi surface in agreement to ARPES data.
WOS
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Dudnikov V. A., Ovchinnikov S. G., Orlov Yu.S., Kazak N. V., Michel C. R., Patrin G. S., Yurkin G.Yu.
Заглавие : Contribution of Co3+ ions to the high-temperature magnetic and electrical properties of GdCoO3
Место публикации : J. Exp. Theor. Phys.: MAIK Nauka-Interperiodica / Springer, 2012. - Vol. 114, Is. 5. - P.841-849. - ISSN 1063-7761, DOI 10.1134/S106377611203003X
Примечания : Cited References: 28. - This work was supported by the Ural Branch of the Russian Academy of Sciences and Siberian Branch of the Russian Academy of Sciences (project no. 40), the Russian Foundation for Basic Research (project nos. 09-02-00171-a, 10-02-00251), program 2.3 of the Department of Physical Sciences of Russian Academy of Sciences, and Nonprofit Dinastiya Foundation.
Предметные рубрики: SPIN-STATE
RCOO3 R
TRANSITIONS
COBALTITES
LACOO3
OXIDES
SM
EU
ND
Аннотация: The temperature dependence of the static magnetization of polycrystalline rare-earth cobaltite GdCoO3 is measured in the temperature range 2-800 K. The magnetic behaviors of GdCoO3 and Gd3+ are found to be different at temperatures above room temperature, which is caused by the appearance of a contribution from Co3+ ions at high temperatures. The temperature dependence of the magnetic susceptibility of GdCoO3 is determined by the magnetization of rare-earth gadolinium ions and the additional paramagnetic contribution induced by the thermally excited magnetic terms of Co3+ ions. The LDA + GTB method is used to calculate the electronic structure of GdCoO3 in the temperature range 0-300 K with allowance for strong electron correlations. The energy spectrum of GdCoO3 is found to have intragap states that decrease the dielectric gap width with increasing temperature.
Смотреть статью,
Scopus,
WoS,
РИНЦ,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G., Gavrichkov V. A., Korshunov M. M., Shneyder E. I.
Заглавие : Electron structure and electron-phonon interaction in the strongly correlated electron system of cuprates
Место публикации : Low Temp. Phys. - 2006. - Vol. 32, Is. 4-5. - P.483-488. - ISSN 1063-777X, DOI 10.1063/1.2199450; \b Физика низких температур
Примечания : Cited References: 37
Предметные рубрики: HIGH-TEMPERATURE SUPERCONDUCTORS
HIGH-TC SUPERCONDUCTIVITY
C SUPERCONDUCTORS
J MODEL
BAND
REPRESENTATION
REGIME
OXIDES
Аннотация: The generalized tight-binding method presents a practical realization of the scheme that describes quasiparticles in a strongly correlated electron system and consists of exact intra-cell diagonalization of the model Hamiltonian and perturbative treatment of the inter-cell hoppings. In the present paper this method and its ab initio modification are applied to undoped and weakly doped HTSC cuprates. Results are in very good agreement with the experimental ARPES data on various compounds. Starting with a multiband p-d model the realistic effective low-energy Hamiltonian of strongly correlated electrons interacting with spin fluctuations and phonons is derived both for hole- and electron-doped systems. Without electron-phonon interaction the pure magnetic mechanism of pairing does not provide the correct value of T, even for single-layer La2-xSrxCuO4 and Nd2-xCexCuO4. (c) 2006 American Institute of Physics.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ma L., Xia Z., Atuchin V. V., Molokeev M. S., Auluck S., Reshak A. H., Liu Q.
Заглавие : Engineering oxygen vacancies towards self-activated BaLuAlxZn4-xO7-(1-x)/2 photoluminescent materials: An experimental and theoretical analysis
Место публикации : Phys. Chem. Chem. Phys.: Royal Society of Chemistry, 2015. - Vol. 17, Is. 46. - P.31188-31194. - ISSN 14639076 (ISSN), DOI 10.1039/c5cp05130d
Примечания : Cited References: 28. - The present work was supported by the National Natural Science Foundations of China (Grant No. 51572023, 51272242 and 51511130035), and Fundamental Research Funds for the Central Universities (FRF-TP-15-005A1). The author A. H. Reshak 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 programme 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. SA would like to thank CSIR-NPL and Physics Department IIT Delhi for financial support. This work was partly supported by the Russian Foundation for Basic Research (Grant No. 15-52-53080 GFEN_a). VVA was partly supported by the Ministry of Education and Science of the Russian Federation.
Предметные рубрики: PHOSPHOR
LUMINESCENCE
EVOLUTION
OXIDES
IONS
Аннотация: Novel self-activated yellow-emitting BaLuAlxZn4-xO7-(1-x)/2 photoluminescent materials were investigated by a combined experimental and theoretical analysis. The effects of Al/Zn composition modulation, calcination atmosphere and temperature on the crystal structure and photoluminescence properties have been studied via engineering oxygen vacancies. Accordingly, BaLuAl0.91Zn3.09O7 prepared in an air atmosphere was found to be the stable crystalline phase with optimal oxygen content and gave a broad yellow emission band with a maximum at 528 nm. The self-activated luminescence mechanism is ascribed to the O-vacancies based on the density functional theory (DFT) calculation. A theoretical model originating from the designed oxygen vacancies has been proposed in order to determine the influence of O-vacancies on the band structure and self-activated luminescence. Therefore, the appearance of a new local energy level in the band gap will cause the wide-band optical transitions in the studied BaLuAlxZn4-xO7-(1-x)/2 materials.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Troyanchuk I. O., Bushinsky M. V., Sikolenko V., Efimov V., Volkov N. V., Tobbens D. M., Ritter C., Raveau B.
Заглавие : Ferromagnetism in single-valent manganites
Место публикации : J. Alloys Compd.: Elsevier Science, 2015. - Vol. 619. - P.719-725. - ISSN 0925-8388, DOI 10.1016/j.jallcom.2014.08.236. - ISSN 1873-4669
Примечания : Cited References: 46. - The authors would like to thank J.B. Goodenough for the fruitful discussion. This work has been supported by Belarusian Republican Foundation for Fundamental Research (Grant F14R-040).
Предметные рубрики: PHASE-SEPARATION
DOPED MANGANITES
DOUBLE EXCHANGE
DIFFRACTION
OXIDES
NMR
Ключевые слова (''Своб.индексиров.''): magnetically ordered materials--solid state reactions--exchange and superexchange--magnetic measurements--neutron diffraction
Аннотация: Structural and magnetization measurements have been performed on the La0.7Sr0.3Mn0.85 Nb 0.15 - x 5 + Mg x 2 + O3 stoichiometric compounds. With rise of the Mg2+ content the formal oxidation state manganese increases from +3 ( x = 0 ) up to +3.55 ( x = 0.15 ) . The compositions with 0 ⩽ x ≤ 0.08 undergo a structural transition from rhombohedral to orthorhombic symmetry below room temperature whereas x = 0.1 and x = 0.15 compounds are rhombohedral down to 2 K. The structural parameters evidence that the orthorhombic phase is not long-range orbitally ordered and that the structural transition is associated with a steric effect. The Mg-free compound is ferromagnetic with the Curie point of around 150 K and a magnetic moment of 3.1 μ B /Mn. The substitution of Nb5+ with Mg2+ leads to a gradual weakening of the ferromagnetic component while in the x = 0.15 compound A-type antiferromagnetic short-range order is stabilized in spite of macroscopic R 3 ¯ c symmetry. All the compositions show insulating behavior. It is suggested that ferromagnetism is originated from superexchange interactions via oxygen. Covalence enhances the positive part of the superexchange interactions whereas structural disorder induced by Nb5+ and Mg2+ ions leads to suppression of ferromagnetism.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gavrichkov V. A., Kuz'min E. V., Ovchinnikov S. G.
Заглавие : Electronic structure and order parameter symmetry in high-temperature superconductors
Место публикации : Uspekhi Fiz. Nauk: MEZHDUNARODNAYA KNIGA, 2000. - Vol. 170, Is. 2. - P.189-192. - ISSN 0042-1294
Примечания : Cited References: 31
Предметные рубрики: CORRELATED ELECTRONS
HUBBARD-MODEL
OXIDES
LA2-XSRXCUO4
WOS,
Читать в сети ИФ
Найти похожие

10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G., Orlov Yu. S., Kuzubov A. A., Dudnikov V. A., Sokolov A. E., Zabluda V. N., Naumov S. B., Shestakov N. P.
Заглавие : Giant red shift of the absorption spectra due to nonstoichiometry in GdCoO3–δ
Коллективы : Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific Schools [NSh-2886.2014.2]; Presidium of Russian Academy of Sciences [34]; Russian Foundation for Basic Research [16-02-00507, 16-02-00273, 16-02-00098, 14-02-00186]; Internationale Buro, Bundesministerium fur Bildung und Forschung (BMBF) [05K12GU2]
Место публикации : JETP Letters. - 2016. - Vol. 103, Is. 3. - P.161-166. - ISSN 0021-3640, DOI 10.1134/S0021364016030115. - ISSN 1090-6487(eISSN)
Примечания : Cited References:40. - This work was supported by the Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific Schools (project no. NSh-2886.2014.2), by the Presidium of Russian Academy of Sciences (Program 34), by the Russian Foundation for Basic Research (project nos. 16-02-00507, 16-02-00273, 16-02-00098, and 14-02-00186), and by Internationale Buro, Bundesministerium fur Bildung und Forschung (BMBF, grant no. 05K12GU2).
Предметные рубрики: TRANSITION-METAL COMPOUNDS
TOTAL-ENERGY CALCULATIONS
AUGMENTED-WAVE METHOD
ELECTRONIC-STRUCTURE
MAGNETIC-PROPERTIES
SPIN TRANSITION
BAND-GAPS
BASIS-SET
LaCoO3
OXIDES
Аннотация: The GdCoO3–δ perovskite is a semiconductor with the energy gap Eg ≈ 0.5 eV from electrical transport measurements. It reveals unusual optical absorption spectra without transparency window expected for semiconductors. Instead we have measured the narrow transmittance peak at the photon energy ε0 = 0.087 eV. To reconcile the transport and optical data we have studied the effect of oxygen vacancies on the electronic structure of the GdCoO3–δ. We have found that oxygen vacancies result in the in-gap states inside the charge-transfer energy gap of the GdCoO3. It is a multielectron effect due to strong electron correlations forming the electronic structure of the GdCoO3–δ. These in-gap states decrease the transparency window and result in a narrow absorption minimum. The predicted temperature dependence of the absorption spectra has been confirmed by our measurements.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Denisova L. T., Chumilina L. G., Shaikhutdinov K. A., Patrin G. S., Denisov V. M.
Заглавие : Heat capacity and thermodynamic properties of HoMnO3 in the range of 364–1046 K
Место публикации : Phys. Solid State: MAIK Nauka-Interperiodica / Springer, 2016. - Vol. 58, Is. 3. - P.481-484. - ISSN 1063-7834, DOI 10.1134/S1063783416030070. - ISSN 1090-6460(eISSN)
Примечания : Cited References:27
Предметные рубрики: High-temperature
Rare-earth
YMnO3
Oxides
System
Аннотация: The temperature dependence of the molar heat capacity of HoMnO3 has been measured by differential scanning calorimetry. The experimental data have been used to calculate the thermodynamic properties of the oxide compound (changes in the enthalpy H°(T)–H°(364 K), entropy S°(T)–S°(364 K), and reduced Gibbs energy Φ°(T)). The data on the heat capacity of HoMnO3 have been generalized in the range of 40–1000 K.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Denisov V. M., Denisova L. T., Irtyugo L. A., Volkov N. V., Patrin G. S., Chumilina L. G.
Заглавие : High-temperature heat capacity of copper metaborate CuB2O4
Место публикации : Phys. Solid State: MAIK Nauka-Interperiodica / Springer, 2012. - Vol. 54, Is. 10. - P.2142-2144. - ISSN 1063-7834, DOI 10.1134/S1063783412100113
Примечания : Cited References: 17
Предметные рубрики: SINGLE-CRYSTALS
MAGNETIC-PROPERTIES
SYSTEM
OXIDES
Аннотация: The heat capacity of copper metaborate CuB2O4 has been measured over a wide temperature range. A correlation between the composition of the CuO-B2O3 system and the heat capacity of the oxide compounds has been found.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Denisov V. M., Denisova L. T., Irtyugo L. A., Patrin G. S., Volkov N. V., Chumilina L. G.
Заглавие : High-temperature heat capacity of Y2.93Ho0.07Fe5O12
Место публикации : Phys. Solid State: MAIK Nauka-Interperiodica / Springer, 2012. - Vol. 54, Is. 11. - P.2205-2207. - ISSN 1063-7834, DOI 10.1134/S1063783412110078
Примечания : Cited References: 28
Предметные рубрики: PHYSICAL-PROPERTIES
SYSTEM
OXIDES
Аннотация: This paper presents data on the heat capacity of Y2.93Ho0.07Fe5O12 obtained in the temperature range 343-1000 K. A correlation between the composition of the Fe2O3-Y2O3 pseudobinary system and the specific heat capacity of oxide compounds is pointed out.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vereshchagin S. N., Solovyov L. A., Rabchevskii E. V., Dudnikov V. A., Ovchinnikov S. G., Anshits A. G.
Заглавие : Methane oxidation over A-site ordered and disordered Sr0.8Gd0.2CoO3−δ perovskites
Коллективы : SB RAS project [38]; RFBR [13-02-00358]
Место публикации : Chem. Commun.: Royal Society of Chemistry, 2014. - Vol. 50, Is. 46. - P.6112-6115. - ISSN 1359-7345, DOI 10.1039/c4cc00913d. - ISSN 1364-548X
Примечания : Cited References: 20. - The authors acknowledge the financial support from SB RAS project N 38 (2012) and RFBR grant 13-02-00358.
Предметные рубрики: MEMBRANE REACTORS
OXYGEN
OXIDES
PERFORMANCE
COMBUSTION
FEATURES
PHASES
Аннотация: A tetragonal phase Sr0.8Gd0.2CoO3−δ with ordered Gd3+/Sr2+ ions and oxygen vacancy sites is found to be about five times less active in the reaction of methane combustion than a quenched cubic perovskite phase with randomly distributed (disordered) Gd3+/Sr2+ ions over the A-sites of the crystal lattice.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Abramova G. M., Petrakovskii G. A., Bayukov O. A., Varnek V. A., Sokolov V. V., Bovina A. F.
Заглавие : Mossbauer studies of FexMn1-xS single crystals
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2008. - Vol. 50, Is. 2. - P237-240. - ISSN 1063-7834, DOI 10.1134/S1063783408020042
Примечания : Cited References: 16
Предметные рубрики: METAL-INSULATOR-TRANSITION
MAGNETIC-PROPERTIES
ALPHA-MNS
SULFIDES
MAGNETORESISTANCE
PRESSURE
SYSTEM
OXIDES
Аннотация: Single crystals of iron manganese sulfides FexMn1-xS (0.25
WOS,
Читать в сети ИФ
Найти похожие

16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Liu C., Xia, Zhiguo, Chen M., Molokeev M. S., Liu Q.
Заглавие : Near-infrared luminescence and color tunable chromophores based on Cr3+-Doped Mullite-Type Bi2(Ga,Al)4O9 solid solutions
Место публикации : Inorg. Chem.: American Chemical Society, 2015. - Vol. 54, Is. 4. - P.1876-1882. - ISSN 0020-1669, DOI 10.1021/ic502779d
Примечания : Cited References: 26. - The present work was supported by the National Natural Science Foundations of China (Grants 51002146, 51272242), 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), Beijing Youth Excellent Talent Program (YETP0635), the Funds of the State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University (KF201306), and Fundamental Research Funds for the Central Universities (FRF-TP-14-005A1).
Предметные рубрики: PERSISTENT LUMINESCENCE
PHOSPHORS
PIGMENT
GARNET
OXIDES
FIELD
RED
Аннотация: Cr3+-activated mullite-type Bi2Ga(4-x)AlxO9 (x = 0, 1, 2, 3, and 4) solid solutions were prepared by the solid state reaction, and their spectroscopic properties were investigated in conjunction with the structural evolution. Under excitation at 610 nm, Bi2[Ga(4-y)Aly]3.97O9:0.03Cr3+ (y = 0, 1, 2, 3, and 4) phosphors exhibited broad-band near-infrared (NIR) emission peaking at ?710 nm in the range 650?850 nm, and the optimum Cr3+ concentrations and concentration quenching mechanism were determined. Except for the interesting NIR emission, the body color changed from white (at x = 0) to green (at x = 0.08) for Bi2Ga4?xO9:xCr3+, and from light yellow (at x = 0) to deep brown (at x = 0.08) for Bi2Al4?xO9:xCr3+, respectively. Moreover, as a result of variable Al/Ga ratio, the observed body color for Bi2[Ga(4-y)Aly]3.97O9:0.03Cr3+ (y = 0, 1, 2, 3, and 4) varied from deep brown to green. The relationship between the observed colors and their diffuse reflectance spectra were also studied for the understanding of the different absorption bands. The results indicated that Cr3+-doped Bi2Ga(4-x)AlxO9 solid solutions appeared as the bifunctional materials with NIR phosphors and color-tunable pigments.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Tarakina N. V., Tyutyunnik A. P., Bazuev G. V., Vasiliev A. D., Berger I. F., Gould C., Nikolaenko I. V.
Заглавие : New hexagonal perovskite with Mn4+ and Mn5+ at distinct structural positions
Коллективы : Electron Microscopy and Analysis Group Conference
Место публикации : J. Phys.: Conf. Ser./ Electron Microscopy and Analysis Group Conference (2015 ; Jun 02-Jul 02 ; Manchester, England): IOP Publishing, 2015. - Vol. 644. - Ст.UNSP 012004. - ISSN 1742-6588, DOI 10.1088/1742-6596/644/1/012004
Примечания : Cited References:13
Предметные рубрики: MAGNETIC-PROPERTIES
OXIDES
PHASES
Аннотация: A new hexagonal perovskite, Ba7Li1.75Mn3.5O15.75, has been synthesised using microwave-assisted solid-state synthesis. Its crystal structure has elements typical for the layered hexagonal perovskites and quasi-one-dimensional oxides, hence representing a new polytype. Structural solution based on simultaneous refinement of X-ray and neutron diffraction data shows that Ba7Li1.75Mn3.5O15.75 crystallizes in a hexagonal unit cell with parameters a = 5.66274(2) Å and c = 16.7467(1) Å ( V = 465.063(4) Å3). Columns of face- shared octahedra occupied by Mn4+, Li+ cations and vacancies along the c axis are separated in the ab plane by barium atoms, so that every sixth layer, the coordination of Mn5+ and Li+ changes to tetrahedral. Separation of Mn4+ and Mn5+ cations in two distinct structural positions makes the structure unique. A scanning transmission electron microscopy study revealed the formation of a rhombohedrally centered supercell, which might be attributed to the ordering of manganese and lithium atoms among cationic sites.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vereshchagin S. N., Solov'ev L. A., Rabchevskii E. V., Dudnikov V. A., Ovchinnikov S. G., Anshits A. G.
Заглавие : New method for regulating the activity of ABO3 perovskite catalysts
Коллективы : Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific Schools [NSh-2886.2014.2]
Место публикации : Kinet. Catal.: MAIK Nauka-Interperiodica / Springer, 2015. - Vol. 56, Is. 5. - P.640-645. - ISSN 0023, DOI 10.1134/S0023158415040199. - ISSN 16083210(eISSN)
Примечания : Cited References:23. - This work was supported in part by the Council of the President of the Russian Federation for Support of Young Scientists and Leading Scientific Schools (grant no. NSh-2886.2014.2).
Предметные рубрики: MEMBRANE REACTORS
METHANE COMBUSTION
OXIDATION
OXIDES
OXYGEN
PERFORMANCE
FEATURES
PHASES
CO
Ключевые слова (''Своб.индексиров.''): perovskite--cobalt--methane--deep oxidation--oxidative condensation
Аннотация: A new possibility of changing the activity and selectivity of perovskite catalysts in the oxidative conversion of methane was demonstrated using the Sr x Gd1–x CoO3–δ (0.5 x 0.9) compounds as an example. It was established that, at the same chemical composition, the disordering of Sr2+/Gd3+ ions over the A positions of the crystal structure led to a significant increase in activity in the deep oxidation reaction of CH4, as compared with the samples with an ordered distribution of cations.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Orlov Y. S., Ovchinnikov S. G.
Заглавие : Construction of a Multielectron Basis for Mott Insulators with Strong Electron Correlations, Spin-Orbit Interaction, and Covalence
Место публикации : J. Exp. Theor. Phys. - 2009. - Vol. 109, Is. 2. - P.322-338. - ISSN 1063-7761, DOI 10.1134/S1063776109080196
Примечания : Cited References: 35
Предметные рубрики: NARROW ENERGY BANDS
MAGNETIC ANISOTROPY ENERGY
ORIGIN
TRANSITION
PHYSICS
MANGANITES
OXIDES
CHARGE
Аннотация: We propose that the apparatus of quantum mechanics of a free atom (in particular, the theory of nj symbols and Rakah-Wigner genealogic coefficients generalized to the case of point groups and widely used in crystal field theory) be used for constructing multielectron bases with allowance for covalence and spin-orbit interaction. This allows us to take into account the electron-electron interaction for 3d ions the most comprehensively. The basis constructed in this way can be used in the generalized strong coupling method for the multiband p-d model in describing the structure of the quasiparticle energy spectrum and physical properties of systems with strong electron correlations. The procedure of construction and computation is demonstrated for the (5)T(2g) term in the d(6) configuration of the transition metal atom in an octahedral field. The mechanism for the emergence of magnetic anisotropy in S ions (Fe(3+) and Mn(2+)) due to covalent mixing of d(6) (L) under bar configurations with a nonzero orbital angular momentum ((L) under bar is a hole in ligands) is demonstrated
WOS,
Смотреть статью,
Читать в сети ИФ
Найти похожие

20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ovchinnikov S. G., Shneider E. I.
Заглавие : Effective Hamiltonian for HTSC cuprates taking into account electron-phonon interaction in the strong-correlation regime
Место публикации : J. Exp. Theor. Phys.: AMER INST PHYSICS, 2005. - Vol. 101, Is. 5. - P844-855. - ISSN 1063-7761, DOI 10.1134/1.2149064
Примечания : Cited References: 38. - This work was supported by the Russian Foundation for Basic Research (project no. 03-02-16124), the program “Quantum Macrophysics” of the Presidium of the Russian Academy of Sciences, the Foundation in Support for Russian Science, the Foundation of Noncommercial
Предметные рубрики: HIGH-TEMPERATURE SUPERCONDUCTORS
D-WAVE SUPERCONDUCTIVITY
T-C
DISPERSION
SCATTERING
OXIDES
STATE
MODEL
Ключевые слова (''Своб.индексиров.''): electron beams--electronic structure--optimization--phonons--electron correlations--hubbard x operators--spin-photon interaction--hamiltonians
Аннотация: Electron-phonon interaction is sequentially derived from a realistic p-d multiband model for the cuprates under conditions of strong electron correlations. The electronic structure is described using the representation of the Hubbard X operators in a generalized tight-binding method. Dependences of the diagonal and off-diagonal (on lattice sites) matrix elements of electron-phonon interaction on the wavevectors are found for three phonon modes, namely, breathing, apical breathing, and bending modes. The interactions of the breathing and bending modes with electrons are shown to contribute to the formation of kinks in the (0; 0)-(pi; pi) and (0; 0)-(pi; 0) directions, respectively. A low-energy t-J* model with phonons is developed; apart from electron-phonon interaction, it also includes spin-phonon interaction. The elimination of phonons gives an effective electron-electron interaction that depends on the occupation number of a multielectron term and on the carrier concentration due to strong electron correlations. (c) 2005 Pleiades Publishing, Inc.
WOS,
Scopus,
РИНЦ,
Смотреть статью,
Читать в сети ИФ
Найти похожие