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

Найдено в других БД:

Каталог книг и брошюр библиотеки ИФ СО РАН (30)

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>A=Aver'yanov, E. M.$<.>)

Общее количество найденных документов : 112
Показаны документы с 1 по 20

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Anisotropy of dipole-dipole interactions in ferroelectric langmuir films of poly(vinylidene fluoride-trifluoroethylene)
Место публикации : JETP Letters. - 2014. - Vol. 99, Is. 10. - P.590-593. - ISSN 0021-3640, DOI 10.1134/S0021364014100026. - ISSN 1090-6487
Примечания : Cited References: 12
Предметные рубрики: LOCAL-FIELD
BLODGETT-FILMS
COPOLYMER
Аннотация: The Lorentz tensor components L (j) for poly(vinylidene fluoride-trifluoroethylene, 70/30) Langmuir-Blodgett films in the ferroelectric phase are determined experimentally. The results indicate that intralayer dipole-dipole interaction between the segments of the polymer is stronger than interlayer interaction. This conclusion agrees with the absence of the critical film thickness below which ferroelectricity would cease to exist.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Anisotropy of the Local Field in Anisotropic Films of Conjugated Polymers
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2011. - Vol. 53, Is. 9. - P1933-1942. - ISSN 1063-7834, DOI 10.1134/S1063783411090046
Примечания : Cited References: 51
Предметные рубрики: MOLECULAR-WEIGHT DEPENDENCE
OPTICAL-PROPERTIES
THIN-FILMS
MEH-PPV
POLY(P-PHENYLENE VINYLENE)
CHAIN ORIENTATION
REFRACTIVE-INDEX
CONSTANTS
POLYACETYLENE
LIGHT
Аннотация: Using the data on dispersion of refractive indices in the visible region, the experimental values of the components L-j of the Lorentz tensor have been obtained for uniaxial (crystalline, oriented on a substrate, and stretched) films of conjugated polymers from nanometer to micrometer thicknesses. The dependence of the components L-j on the axial and planar orientations of macromolecules with respect to the optical axis of the film, technology of fabricating the films, and chemical structure of macromolecules has been elucidated. The correlation between the components L-j and the measured parameter. has been determined and the analytical dependence L-j(eta) for films with both types of macromolecular orientation has been established. In the visible region (0
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Change in the polarizability of MBBA molecules upon the nematic-isotropic liquid transition and physical consequences
Место публикации : Phys. Solid State. - 2013. - Vol. 55, Is. 10. - P.2136-2141. - ISSN 1063-7834, DOI 10.1134/S106378341310003X
Аннотация: The Lorentz tensor components Lj and the polarizability tensor components ?j of 4-methoxyben-zylidene-4?-butylaniline (MBBA) liquid crystal molecules in nematic and isotropic phases have been determined experimentally. The quadratic dependences of the mean value ?(S) and anisotropy ??(S) of the polarizability in the nematic phase on the orientational order parameter S of molecules have been established. Within the phenomenological approach, the dependences ?(S) and ??(S) have been derived, and their features for MBBA and other known objects have been interpreted. The relation of the dependences ?(S) and ??(S) to the features of the nematic-isotropic liquid phase transition has been found. В© 2013 Pleiades Publishing, Ltd.
Scopus,
WoS,
Смотреть статью,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Change in the polarizability of molecules at the phase transitions isotropic liquid -nematic - smectic-A - crystal-B in liquid crystal 4О.8
Коллективы : European Conference on Liquid Crystals, Московский государственный университет им. М.В. Ломоносова
Место публикации : 14th Eur. Conf. Liq. Cryst. (ECLC): conf. programme/ чл. нац. орг. и прогр. ком. V. Ya. Zyryanov. - 2017. - Ст.P3. - Poster
Примечания : Библиогр.:
Материалы конференции,
Материалы конференции
Найти похожие

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Change in the spectrum of the polarizability density of molecules at the smectic-A - crystal-B phase transition
Коллективы : European Conference on Liquid Crystals, Московский государственный университет им. М.В. Ломоносова
Место публикации : 14th Eur. Conf. Liq. Cryst. (ECLC): conf. programme/ чл. нац. орг. и прогр. ком. V. Ya. Zyryanov. - 2017. - Ст.P4. - Poster
Примечания : Библиогр.:
Материалы конференции,
Материалы конференции
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Correlation of the molecular structure of discotic nematic liquid crystals with their orientational order and specific features of the nematic-isotropic phase transition
Место публикации : Phys. Solid State: AMER INST PHYSICS, 2004. - Vol. 46, Is. 8. - P1554-1559. - ISSN 1063-7834, DOI 10.1134/1.1788794
Примечания : Cited References: 32
Предметные рубрики: MONTE-CARLO
ANISOTROPIC SYSTEMS
COMPUTER-SIMULATION
BEHAVIOR
TRIPHENYLENE
DISCOGEN
MESOGEN
FIELD
Аннотация: The orientational order parameter S of molecules in high-temperature discotic nematic liquid-crystal phases of triphenylene derivatives is investigated as a function of the length of side flexible molecular chains at different temperatures. It is established that the orientational order parameters S in the range of the transition from the nematic phase to the isotropic liquid phase (the N-D-I transition) are smaller than those predicted from the molecular-statistical theory and computer simulation. It is shown that the N-D-I transition is close to both the isolated Landau point and the tricritical point (regardless of the chemical structure of the molecules and the anisotropy of dispersion intermolecular interactions). Consistent explanations are offered for a number of experimental findings, such as the anomalously small changes in the enthalpy and entropy upon the N-D-I transition (as compared to those revealed upon the N-I transition in calamitic nematic liquid crystals), the anomalously strong response of the isotropic phase of discotic nematic liquid crystals to external fields (thermodynamically conjugate to the order parameter S) and the long relaxation times of this response, and the formation of cybotactic discotic molecular clusters in the isotropic phase in the vicinity of the N-D-I transition. (C) 2004 MAIK "Nauka / Interperiodica".
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Dimension of mesogenic molecules as atomic clusters
Место публикации : Phys. Solid State: AMER INST PHYSICS, 2005. - Vol. 47, Is. 2. - P378-389. - ISSN 1063-7834, DOI 10.1134/1.1866424
Примечания : Cited References: 19
Предметные рубрики: LIQUID-CRYSTAL CHEMISTRY
ORIENTATIONAL ORDER
TRANSITION
Аннотация: The problem regarding the mass dimension D of mesogenic molecules as atomic clusters is formulated and solved using computer simulation and analytical calculations. For a large number of compounds belonging to different chemical classes, it is shown that the cores of discotic lacunar (rodlike, lathlike) molecules forming nematic or columnar discotic (calamitic) phases have a fractional dimension 1 D-c 2 (D-c approximate to 1). The dependences of the dimension D-c on the symmetry, the conformation, and the structural-chemical features of the molecular core are determined. It is demonstrated that, in the region of side flexible chains in molecules of both types, the dimension D-ch can be either smaller or larger than unity, depending on the chain conformation. An analytical expression accounting for the results of numerical experiments is obtained for the dimension D-ch. (C) 2005 Pleiades Publishing, Inc.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Effective refractive index of a quasi-two-dimensional polydomain film of a conjugated polymer
Место публикации : Phys. Solid State: MAIK Nauka-Interperiodica / Springer, 2016. - Vol. 58, Is. 1. - P.160-163. - ISSN 10637834 (ISSN), DOI 10.1134/S1063783416010042
Примечания : Cited References: 20
Предметные рубрики: THIN POLYFLUORENE FILMS
OPTICAL-CONSTANTS
LOCAL-FIELD
ANISOTROPY
ORDER
Аннотация: The relation between the effective ordinary refractive index n* = (n o n e )1/2 of a quasi-two-dimensional polydomain uniaxial film of a conjugated polymer F8BT in the visible transparency region and the refractive indices (n o,e ) of uniaxial domains with the optical axes randomly oriented in the plane of the film has been confirmed experimentally. The permissible interval of variations in n* has been established and a strong spectral dispersion of this interval near the long-wavelength electronic absorption band of the film has been demonstrated.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Effective refractive index of a two-dimensional polycrystal
Место публикации : JETP Letters. - 2015. - Vol. 101, Is. 10. - P.685-689. - ISSN 0021-3640, DOI 10.1134/S0021364015100033
Примечания : Cited References: 28
Предметные рубрики: SPECTROSCOPIC ELLIPSOMETRY
CONJUGATED POLYMERS
LOCAL-FIELD
FILMS
CONDUCTIVITY
POLYFLUORENE
ANISOTROPY
DISPERSION
MEDIA
Аннотация: A relation of the effective refractive index of a two-dimensional polycrystalline dielectric film in the transparency region to the refractive indices n1 and n2 of crystallites at the positions of axes 1 and 2, respectively, of refraction ellipsoids of the crystallites in the plane of the film has been obtained. This relation and the relation L* = (L1 + L2)/2 between the components of the Lorentz tensors for the film and crystallites have been confirmed by comparison with experimental data for conjugate-polymer films with uniaxial domains.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Fluctuations of orientational order in a uniaxial nematic liquid crystal with biaxial molecules and its response to an external field
Место публикации : Phys. Solid State: AMER INST PHYSICS, 2003. - Vol. 45, Is. 5. - P990-1001. - ISSN 1063-7834, DOI 10.1134/1.1575350
Примечания : Cited References: 30
Предметные рубрики: PHASE-TRANSITION
SMECTIC-A
PARTICLES
SYSTEM
LANDAU
MODEL
Аннотация: Homogeneous thermal fluctuations of the orientational order parameters S and G of biaxial molecules in a uniaxial nematic liquid crystal are investigated in the framework of the molecular-statistical theory. It is demonstrated that the molecular biaxiality significantly affects the order parameters S and G, their temperature dependences in the nematic phase, the amplitude and the temperature dependence of the order parameter fluctuations in the nematic and isotropic phases, and the character of the transition from the nematic phase to the isotropic liquid phase. It is established that the fluctuations of the parameters S and G in the nematic phase are related to the temperature dependences of S and G and the susceptibilities chi(S) and chi(G) of the nematic liquid crystal to external fields, which leads to a change in the parameters S and G at a fixed director orientation. Explanations are offered for the known experimental data on the orientational ordering of biaxial molecules under the action of external fields in the isotropic phase of nematic liquid crystals. (C) 2003 MAIK "Nauka/Interperiodica".
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Influence of nematic and smectic orders on polarizability of molecules of ethyl-p-(4-ethoxybenzylideneamino-)alpha-methyl cinnamate liquid crystals
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2013. - Vol. 55, Is. 11. - P.2391-2396. - ISSN 1063-7834, DOI 10.1134/S1063783413110048
Примечания : Cited References: 16
Предметные рубрики: TRANSITION
MBBA
Аннотация: Experimental values of the polarizability tensor gamma components of molecules of ethyl-p-(4-ethoxybenzylideneamino-)alpha-methyl cinnamate liquid crystals in the nematic and smectic A phases have been obtained. Quadratic dependences of the longitudinal, gamma (l) , and transverse, gamma (t) , components, the mean value , and anisotropy Delta gamma in both phases have been established as functions of the orientational order parameter S of molecules in a maximally wide range of S. The nematic-smectic A phase transition with a continuous variation of S manifests itself as kinks in the linear dependences of , Delta gamma, and gamma (l) on S (2) and does not influence the dependence gamma (t) (S (2)). The observed dependences have been derived in the framework of the theory of the nematic-smectic A phase transition. The factors responsible for different influences of the orientational and positional orderings of molecules on the polarizability parameters have been determined.
WOS,
Смотреть статью,
WOS,
Читать в сети ИФ
Найти похожие

12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Influence of the dimension of a polycrystalline film and the optical anisotropy of crystallites on the effective dielectric constant of the film
Место публикации : Phys. Solid State: MAIK Nauka-Interperiodica / Springer, 2016. - Vol. 58, Is. 8. - P.1634-1641. - ISSN 10637834 (ISSN), DOI 10.1134/S1063783416080035
Примечания : Cited References: 41
Предметные рубрики: EFFECTIVE REFRACTIVE-INDEX
CONJUGATED POLYMER
POLY(P-PHENYLENE VINYLENE)
SPECTROSCOPIC ELLIPSOMETRY
ELECTRICAL-CONDUCTIVITY
LOCAL-FIELD
THIN-FILMS
DISPERSION
POLYFLUORENE
DEVICES
Аннотация: The dimension D of a polycrystalline film and the optical anisotropy m = εz/εx of uniaxial crystallites with the principal components εx = εy and εz of the tensor of the dielectric constant have been shown to produce a strong influence on the effective dielectric constant εD* and the effective refractive index nD* = (εD*)1/2 of the film in the optical transparency region, as well as on the boundaries of the intervals BDl ≤ εD* ≤ BDu. The intervals Δ2(m) = B2l–B2u and Δ3(m) = B3l–B3u are separated by a gap for m in the range 1 m 2, whereas the theoretical dependence ε2*(m) is separated by a gap from the interval Δ3(m) for m in the range 1 m 4. This is confirmed by a comparison of the experimental (noP) and theoretical (nD*) ordinary refractive indices for uniaxial polycrystalline films of the conjugated polymer poly(p-phenylene vinylene) (PPV) with uniaxial crystallites and appropriate values of m. In the visible transparency region of the PPV films with a change in m(λ) in the range 2 m(λ) 3 due to the dependence of the components εx,z(λ) on the light wavelength λ, the refractive indices noP2(λ) 3 near the electronic absorption band of the crystallites, the values of εoP(λ) lie in the region of the overlap of the intervals Δ2(m) and Δ3(m). The boundaries mc of the range 1 m mc are determined, for which the interval Δ2(m) is separated by a gap from the dependences ε3*(m) corresponding to the effective medium theory with spherical crystallites and hierarchical models of a polycrystal, as well as from the proposed new dependence ε3*(m).
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Local field anisotropy in Langmuir-Blodgett films of cadmium arachidate
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2011. - Vol. 53, Is. 12. - P2492-2494. - ISSN 1063-7834, DOI 10.1134/S1063783411120031
Примечания : Cited References: 9
Предметные рубрики: SPECTROSCOPY
Аннотация: Lorentz tensor and local field tensor components for uniaxial Langmuir-Blodgett films of cadmium arachidate from 3 to 100 nm thick on silver, polymethyl methacrylate, and glass substrates have been experimentally determined using the data on the film refractive index dispersion in the visible range. The constraints from below on the mean value and anisotropy of the molecular polarizability caused by the intermolecular interactions in the film have been established.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Local-field anisotropy in cholesteric liquid crystals
Коллективы : Presidium of the Russian Academy of Sciences; Siberian Branch, Russian Academy of Sciences
Место публикации : JETP Letters. - 2009. - Vol. 89, Is. 7. - P.324-327. - ISSN 0021-3640, DOI 10.1134/S0021364009070030
Примечания : Cited References: 12. - This work was supported by the Presidium of the Russian Academy of Sciences ( Basic Research Program, project no. 27.1) and by the Siberian Branch, Russian Academy of Sciences ( Interdisciplinary Basic Research Program, project no. 5).
Предметные рубрики: ORDER
POLARIZABILITY
Аннотация: The first experimental values of the Lorentz tensor components L (j) for the cholesteric and smectic A phases of derivatives of cholesterol have been obtained using the dispersion of the refractive indices in the visible range. The temperature dependence of the components L (j) has been determined; it is invariant with respect to the cholesteric-smectic A phase transition. The effect of the isotropization of the Lorentz and local field tensors with decreasing anisotropy of the molecular polarizability has been revealed.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Local-field anisotropy in conjugated polymers
Место публикации : JETP Letters. - 2010. - Vol. 91, Is. 9. - P.455-460. - ISSN 0021-3640, DOI 10.1134/S0021364010090055
Примечания : Cited References: 25
Предметные рубрики: OPTICAL-CONSTANTS
THIN-FILMS
LASERS
Аннотация: The experimental values of the Lorentz tensor components L (j) have been obtained for uniaxial optically positive and negative films of conjugated polymers with thicknesses of tens of nanometers. The correlation between the components L (j) and the measurable parameter eta has been revealed and the analytical dependence L (j) (eta) has been derived in agreement with the experiment.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Local-Field Anisotropy of a Light Wave in Quasi-Two-Dimensional Soft-Matter Objects
Коллективы :
Разночтения заглавия :авие SCOPUS: Local-field anisotropy of a light wave in quasi-two-dimensional soft-matter objects
Место публикации : J. Exp. Theor. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2010. - Vol. 110, Is. 4. - P622-636. - ISSN 1063-7761, DOI 10.1134/S1063776110040102
Примечания : Cited References: 73. - This study was supported by the Presidium of the Russian Academy of Sciences within the Program of Basic Research (project no. 27.1) and the Siberian Branch of the Russian Academy of Sciences within the Program of Interdisciplinary Basic Research (project no. 5).
Предметные рубрики: INTEGRATED OPTICAL TECHNIQUES
LANGMUIR-BLODGETT-FILMS
SMECTIC LIQUID-CRYSTALS
UNIAXIAL POLYMER-FILMS
MOLECULAR-ORIENTATION
INTERNAL FIELD
DIELECTRIC-CONSTANT
SPECTRAL FEATURES
REFRACTIVE-INDEX
THIN-FILMS
Ключевые слова (''Своб.индексиров.''): anisotropic films--bilayer lipid membrane--chemical structure--comblike polymers--conductive polymer--discotics--dispersion of refractive index--experimental data--experimental values--hexatic-b phase--isotropization--langmuir films--light wave--lorentz--macromolecular polymers--model approach--molecular polarizabilities--optical axis--order parameter--orientational order parameters--orientational orderings--orientational orders--smectic layers--smectic-a--smectics--soft matter--structural unit--sub-micron films--substrate types--tensor components--visible range--anisotropy--cell membranes--conductive plastics--conjugated polymers--electronic structure--light measurement--liquid crystal polymers--molecules--multilayer films--organic polymers--phase transitions--polarization--polymers--refractive index--substrates--tensors--two dimensional--conductive films
Аннотация: Experimental values of the Lorentz tensor components L-j for uniaxial quasi-two dimensional "soft matter" objects on substrates (bilayer lipid membranes, multilayer Langmuir films, smectics A, hexatic smectics B, submicron films of discotics Col(hd), micron anisotropic films of liquid-crystal comblike polymers and macromolecular polymers, submicron films of conjugated conductive polymers), freely suspended sub-micron films of smectics A, and uniaxially stretched micron films of conjugated conductive polymers have been determined using dispersion of refractive indices in the visible range. The dependences of the components L-j on the type of orientation (axial, planar) of uniaxial molecules (structural units of the film) with respect to the optical axis of the film, the film thickness, the substrate type, the chemical structure of molecules, and their long-range orientational order are established. It is revealed that the smectic A-hexatic B phase transition and two-dimensional crystallization of the smectic layer lead to changes in the components L-j due to the change in the orientational ordering of molecules as a result of the relation between the orientational and hexatic order parameters. All the above objects are characterized by isotropization of the Lorentz tensor L and the local-field tensor f with a simultaneous decrease in the birefringence of the sample and in the anisotropy of the molecular polarizability due to the change in the electronic structure of molecules. The correction for the anisotropy of the local-field tensor f to the orientational order parameter or the anisotropy of the molecular polarizability increases. The existing model approaches to calculating the components L-j for the objects under consideration are compared with the experimental data.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Long-Range Orientational Order, Local-Field Anisotropy, and Mean Molecular Polarizability in Liquid Crystals
Разночтения заглавия :авие SCOPUS: Long-range orientational order, local-field anisotropy, and mean molecular polarizability in liquid crystals
Место публикации : J. Exp. Theor. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2009. - Vol. 108, Is. 1. - P176-186. - ISSN 1063-7761, DOI 10.1134/S106377610901021X
Примечания : Cited References: 35
Предметные рубрики: REFRACTIVE-INDEXES
OPTICAL ANISOTROPY
Ключевые слова (''Своб.индексиров.''): anisotropy--crystal symmetry--crystals--electric fields--light sources--liquid crystals--liquids--molecules--tensors--biaxial liquid crystals--calamitic--discotic--discotic liquid crystals--experimental datum--field models--lorentz--mesoscopic--molecular polarizability--orientational orders--phase state--nematic liquid crystals
Аннотация: The problems on the relation of the mean effective molecular polarizability (gamma) over bar to the long-range orientational order of molecules (the optical anisotropy of the medium) in uniaxial and biaxial liquid crystals, the local anisotropy on mesoscopic scales, and the anisotropy of the Lorentz tensor L and the local-field tensor f are formulated and solved. It is demonstrated that the presence of the long-range orientational order of molecules in liquid crystals imposes limitations from below on the molecular polarizability (gamma) over bar, which differs for uniaxial and biaxial liquid crystals. The relation between the local anisotropy and the molecular polarizability (gamma) over bar is investigated for calamitic and discotic uniaxial liquid crystals consisting of lath- and disk-shaped molecules. These liquid crystals with identical macroscopic symmetry differ in the local anisotropy and the relationships between the components L(parallel to) L(perpendicular to,) f(parallel to) f(perpendicular to) (calamitic) and L(parallel to) L(perpendicular to,) f(parallel to) f(perpendicular to) (discotic) for an electric field oriented parallel and perpendicular to the director. The limitations from below and above on the molecular polarizability (gamma) over bar due to the anisotropy of the tensors L and f are established for liquid crystals of both types. These limitations indicate that the molecular polarizability (gamma) over bar depends on the phase state and the temperature. The factors responsible for the nonphysical consequences of the local-field models based on the approximation (gamma) over bar = const are revealed. The theoretical inferences are confirmed by the experimental data for a number of calamitic nematic liquid crystals with different values of birefringence and the discotic liquid crystal Col(ho).
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M., Rumyantsev V. G.
Заглавие : Manifestations of the higher moments of the orientation distribution function of molecules in the spectral properties of an impurity nematic
Место публикации : J. Exp. Theor. Phys.: AMER INST PHYSICS, 2004. - Vol. 98, Is. 6. - P1146-1151. - ISSN 1063-7761, DOI 10.1134/1.1777627
Примечания : Cited References: 15
Предметные рубрики: LIQUID-CRYSTAL
SCATTERING
PHASES
MATRIX
ORDER
DYES
Ключевые слова (''Своб.индексиров.''): absorption--band structure--impurities--molecular dynamics--polarization--spectrum analysis--distribution function--local field parameters--splitting--temperature dependence--nematic liquid crystals
Аннотация: The polarized electronic absorption spectra, orientation ordering, and the special local field features were studied for push-pull linear dye molecules with strong donor-acceptor electronic conjugation of terminal fragments in the matrix of a nematic liquid crystal. The temperature-induced inversion of the sign of the splitting of polarized impurity absorption bands was observed. This effect was shown to be caused by the statistical character of orientation ordering of impurity molecules and manifestation of the higher moments of the orientation distribution function. The dependence of local field parameters (Lorentz tensor components) of impurity molecules on their orientation ordering was established. This dependence was used to reproduce the temperature dependence of the orientation order parameter of the matrix. (C) 2004 MAIK "Nauka / Interperiodica".
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Mean polarizability of molecules and anisotropy of the Lorentz tensor upon a nematic-smectic a phase transition: Their behavior in a homologous series
Место публикации : Russ. J. Phys. Chem. A: MAIK Nauka-Interperiodica / Springer, 2012. - Vol. 86, Is. 5. - P.720-728. - ISSN 0036-0244, DOI 10.1134/S0036024412050044
Примечания : Cited References: 37
Предметные рубрики: CHOLESTERIC LIQUID-CRYSTALS
REFRACTIVE-INDEX DATA
A PHASE
MESOMORPHIC PROPERTIES
ORIENTATIONAL ORDER
OPTICAL ANISOTROPY
LOCAL-FIELD
POLYMORPHISM
TEMPERATURE
A-monotone
Alkyl chain
Experimental values
Homologous series
Homologues
Limiting values
Lorentz
Mesophases
Molecular core
Molecular polarizabilities
Nematic
Orientational order parameters
Polarizabilities
Polarizability density
Quadratic dependence
A-monotone
Smectic
Smectic phase
Smectic phasis
Smectic-A phasis
Ключевые слова (''Своб.индексиров.''): molecular polarizability--anisotropy--phase transition--nematic--smectic--homologues
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,
Читать в сети ИФ
Найти похожие

20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : New features of a smectic-A-crystal-B phase transition in a homologous series of liquid crystals
Место публикации : JETP Letters. - 2014. - Vol. 99, Is. 3. - P.158-163. - ISSN 0021-3640, DOI 10.1134/S0021364014030047. - ISSN 1090-6487
Примечания : Cited References: 21
Предметные рубрики: POLARIZABILITY
POLYMORPHISM
ANISOTROPY
MOLECULES
BEHAVIOR
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,
Читать в сети ИФ
Найти похожие