Structure studies of the nematic phase formed by bent-core molecules

被引：80

作者：

Vaupotic, N. ^{[1
,2
]}

Szydlowska, J. ^{[3
]}

Salamonczyk, M. ^{[3
]}

Kovarova, A. ^{[4
]}

Svoboda, J. ^{[4
]}

Osipov, M. ^{[5
]}

Pociecha, D. ^{[3
]}

Gorecka, E. ^{[3
]}

机构：

[1] Univ Maribor, Fac Nat Sci & Math, Dept Phys, SLO-2000 Maribor, Slovenia

[2] Jozef Stefan Inst, Ljubljana 1000, Slovenia

[3] Univ Warsaw, Dept Chem, PL-02089 Warsaw, Poland

[4] Inst Chem Technol, Dept Organ Chem, CR-16628 Prague 6, Czech Republic

[5] Univ Strathclyde, Dept Math, Glasgow G1 1XH, Lanark, Scotland

来源：

PHYSICAL REVIEW E | 2009年 / 80卷 / 03期

关键词：

X-RAY-DIFFRACTION; SMECTIC-A; HEXATIC B; MESOPHASE; MESOGENS; ROTATION; ORDER; EPR;

D O I：

10.1103/PhysRevE.80.030701

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

In recent years there are several reports showing that bent-core mesogenic molecules are able to form biaxial nematic phase in which molecular rotation around the long molecular axis is strongly hindered. The x-ray pattern with azimuthally split signals at low angle region of diffraction is usually given as evidence for the biaxial nematic phase. We show experimentally and theoretically that such x-ray pattern is due to the local smectic-C fluctuations ("cybotactic" groups) in the uniaxial nematic phase.

引用

页数：4

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