Труды сотрудников института физики

w10=
Найдено документов в текущей БД: 5

    Mean polarizability of molecules and anisotropy of the Lorentz tensor upon a nematic-smectic a phase transition: Their behavior in a homologous series
/ E.M. Aver'yanov // Russ. J. Phys. Chem. A. - 2012. - Vol. 86, Is. 5. - P. 720-728, DOI 10.1134/S0036024412050044. - Cited References: 37 . - ISSN 0036-0244
РУБ Chemistry, Physical + Anisotropy + Molecules + Phase transitions + Tensors

Аннотация: Experimental values of the mean polarizability of molecules, (gamma) over bar, and components of the Lorentz tensor, L-j, in the nematic and smectic A phases are obtained for a homologous series of n-alkyl-p-(4-ethoxybenzylideneamino)-alpha-methylcinnamates. Dependences of the (gamma) over bar and L-j values on the mesophase temperature, the orientational order parameter S of molecules, and the number n in the homologous series are revealed. The quadratic dependence of (gamma) over bar (S) in the nematic and smectic phases is established that is invariant with respect to the nematic-smectic A transition. Polarizability densities of the molecular core and the alkyl chain are found from the monotone decreasing dependence (gamma) over bar (n)/v (where v is volume per one molecule) in the smectic phase. The presence (or absence) of the odd-even alternation of L-j(n) in the nematic (smectic) phase is shown. A monotone decrease in the Lorentz tensor anisotropy L with an increase in n is revealed in the smectic phase, and limiting values L-j(n -> infinity) are determined.

Смотреть статью,
Scopus,
WoS,
Для получение полного текста обратитесь в библиотеку


Доп.точки доступа:
Аверьянов, Евгений Михайлович

    Raman spectroscopy of natural cordierite at high water pressure up to 5?GPa
/ A. Y. Likhacheva [et al.] // J. Raman Spectrosc. - 2012. - Vol. 43, Is. 4. - P. 559-563, DOI 10.1002/jrs.3060. - Cited References: 38. - We greatly appreciate the critical comments of Prof. R. Kaindl and an anonymous reviewer on this work, and we thank Dr G. Lepezin for providing the cordierite sample. This work was supported by RFBR grant 11-05-01121-a. . - ISSN 0377-0486
РУБ Spectroscopy

Аннотация: The high-pressure behaviour of cordierite, a widespread ring aluminosilicate with channels incorporating fluid compounds (H2O, CO2), is characterized by the absence of phase transitions up to 2.5 GPa. However, the distortion of the ring tetrahedra observed previously at 2.3 GPa is supposed to introduce a phase transition at higher pressure, which has not been checked so far. This work presents a high-pressure Raman spectroscopic study of natural cordierite compressed in water medium up to 4.7 GPa in a diamond anvil cell. At P > 4 GPa, a disordering of both the framework and intrachannel H2O subsystem is apparent from significant broadening of Raman peaks and the evolution of short-range order parameters. This is followed by abrupt shifts of the framework and O–H stretching modes at about 4.5 GPa, indicating a first-order phase transition. Its reversibility is seen from the recovery of the initial spectrum at P < 3 GPa. The shift amplitudes of different framework modes indicate the predominance of distortion over contraction of the framework polyhedra upon this transition. The disordering of the H2O subsystem in the high-pressure phase is likely a consequence of distortion of the channel-forming framework elements, which is supposed to be a driving force of this transition. Copyright © 2011 John Wiley & Sons, Ltd.

Смотреть статью,
Scopus,
WoS,
Для получение полного текста обратитесь в библиотеку

Держатели документа:
[Likhacheva, Anna Yu.
Goryainov, Sergey V.
Bul'bak, Taras A.] RAS, SB, Sobolev Inst Geol Mineral, Novosibirsk 630090 90, Russia
[Krylov, Aleksandr S.] RAS, LV Kirensky Phys Inst, Krasnoyarsk 660036, Russia
[Prasad, Pinnelli S. R.] Natl Geophys Res Inst, Council Sci & Ind Res, Hyderabad 500007, Andhra Pradesh, India

Доп.точки доступа:
Likhacheva, A. Y.; Goryainov, S. V.; Krylov, A. S.; Крылов, Александр Сергеевич; Bul'bak, T. A.; Prasad, PSR

    New features of a smectic-A-crystal-B phase transition in a homologous series of liquid crystals
/ E. M. Aver'yanov // JETP Letters. - 2014. - Vol. 99, Is. 3. - P. 158-163, DOI 10.1134/S0021364014030047. - Cited References: 21 . - ISSN 0021-3640. - ISSN 1090-6487
РУБ Physics, Multidisciplinary

Аннотация: The components L j of the Lorentz tensor and the polarizability density of molecules G in the smectic-A and crystalline-B phases have been determined for homologues of the series of alkyl-p-(4-alkoxybenzylideneamino-)cinnamates. The quantity L j (G) in both phases is a linear (quadratic) function of the orientational order parameter of molecules S, which is invariant (noninvariant) with respect to the A-B transition, which is manifested in the form of jumps δL j and δG and enhancement of the G(S) dependence. An increase in the length of terminal molecular chains and weakening of interlayer correlation of molecules are accompanied by strengthening of the A-B transition of the first order and G(S) dependences in both phases together with an increase in δL j and δG. Change δG and dependence G(S) in the B phase are related to change in the conformation (flattening) of aromatic molecular cores.

Смотреть статью,
Scopus,
WoS,
Для получение полного текста обратитесь в библиотеку


Доп.точки доступа:
Аверьянов, Евгений Михайлович

    Effects of composition modulation on the luminescence properties of Eu3+ doped Li1-xAgxLu(MoO4)2 solid-solution phosphors
/ F. Cheng [et al.] // Dalton Trans. - 2015. - Vol. 44, Is. 41. - P. 18078-18089, DOI 10.1039/c5dt02760h. - Cited References: 42. - The present work was supported by the National Natural Science Foundations of China (Grant No. 51272242, 51572023, 51511130035), 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 Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences (RERU2015022), and the excellent tutor section of the Fundamental Research Funds for the Central Universities of China University of Geosciences, Beijing (2-9-2015-028). This work was also partly supported by the Russian Foundation for Basic Research (Grant No. 15-52-53080 GFEN_a). . - ISSN 1477-9226
   Перевод заглавия: Влияние модуляции состава на люминесцентные свойства твердотельного люминофора Li1-xAgxLu(MoO4)2 допированного Eu3+
РУБ Chemistry, Inorganic & Nuclear

Аннотация: Double molybdate scheelite-type solid-solution phosphors Li1−xAgxLu1−y(MoO4)2:yEu3+ were synthesized by the solid state reaction method, and their crystal structures and luminescence properties were investigated in detail. The composition modulation and structural evolution of this series of samples were studied and the selected AgEu(MoO4)2, AgLu(MoO4)2, LiLu(MoO4)2 and LiEu(MoO4)2 phases were analyzed based on the Rietveld refinement. Depending on the variation of the Li/Ag ratio in Li1−xAgxLu1−y(MoO4)2:yEu3+ phosphors, the difference in the luminescence properties of Li1−xAgxLu1−y(MoO4)2:yEu3+ phosphors was ascribed to two factors, one reason could be assigned to the coupling effect and the nonradiative transition between the energy levels of LixAg1−xLu(MoO4)2 matrices and the activator Eu3+, another could be due to the near ultraviolet energy absorption and transmission efficiency between the charge-transfer (CT) band of O2−–Mo6+ and the 4f → 4f emissive transitions of Eu3+. The ultraviolet-visible diffuse reflection spectra (UV-vis DRS) and Raman spectra analysis were also used to verify the above mechanism.

Смотреть статью,
Scopus,
WOS,
Для получение полного текста обратитесь в библиотеку

Держатели документа:
School of Materials Sciences and Technology, China University of Geosciences, Beijing, China
School of Materials Sciences and Engineering, University of Science and Technology Beijing, Beijing, China
Laboratory of Crystal Physics, Kirensky Institute of Physics, SB RAS, Krasnoyarsk, Russian Federation
Department of Physics, Far Eastern State Transport University, Khabarovsk, Russian Federation
Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, China

Доп.точки доступа:
Cheng, F.; Xia, Zhiguo; Molokeev, M. S.; Молокеев, Максим Сергеевич; Jing, X.

    Magnetic, dielectric, and transport properties of bismuth pyrostannate Bi2(Sn0.9Mn0.1)2O7
/ S. S. Aplesnin [et al.] // Phys. Solid State. - 2017. - Vol. 59, Is. 11. - P. 2268-2273, DOI 10.1134/S1063783417110038. - Cited References:20. - This work was supported by the Russian Foundation for Basic Researchers, the Government of the Krasnoyarsk Region, the Krasnoyarsk regional Foundation for Support of Scientific and Scientific-Engineering activity in the framework of the scientific projects no. 18-52-00045 Bel_a. . - ISSN 1063-7834. - ISSN 1090-6460
РУБ Physics, Condensed Matter

Аннотация: The effect of replacing manganese ions on the structural, dielectric, transport, and magnetic properties of Bi2(Sn0.9Mn0.1)2O7 has been studied and the correlation between them has been determined. The change in the type of thermal processes and the thermopower sign upon polymorphous transitions were detected by differential scanning calorimetry. The paramagnetic Curie temperature and the antiferromagnetic interaction were determined in the martensite and austenite phases. The type of current carriers has been established.

Смотреть статью,
Scopus,
WOS,
Для получение полного текста обратитесь в библиотеку

Держатели документа:
Russian Acad Sci, Krasnoyarsk Sci Ctr, Fed Sci Ctr, Kirensky Inst Phys,Siberian Branch, Akademgorod 50, Krasnoyarsk 660036, Russia.
Reshetnev Siberian State Aerosp Univ, Ul Gazety Krasnoyarskii Rabochii 31, Krasnoyarsk 660014, Russia.
Russian Acad Sci, Krasnoyarsk Sci Ctr, Fed Sci Ctr, Siberian Branch, Akademgorod 50, Krasnoyarsk 660036, Russia.
Natl Acad Sci Belarus, Sci & Pract Mat Res Ctr, Ul P Brovki 19, BY-220072 Minsk, Byelarus.

Доп.точки доступа:
Aplesnin, S. S.; Аплеснин, Сергей Степанович; Udod, L. V.; Удод, Любовь Викторовна; Sitnikov, M. N.; Molokeev, M. S.; Молокеев, Максим Сергеевич; Tarasova, L. S.; Yanushkevich, K. I.; Russian Foundation for Basic Researchers; Government of the Krasnoyarsk Region; Krasnoyarsk regional Foundation for Support of Scientific and Scientific-Engineering activity [18-52-00045 Bel_a]