Dielectric relation in liquid crystals with the nematic and smectic A polymorphism

被引：19
作者：
Urban, S
Novotna, E
Kresse, H
Dabrowski, R
机构：
[1] UNIV HALLE WITTENBERG,INST PHYS CHEM,HALLE,GERMANY
[2] MIL UNIV TECHNOL,WARSAW,POLAND
来源：
MOLECULAR CRYSTALS AND LIQUID CRYSTALS SCIENCE AND TECHNOLOGY SECTION A-MOLECULAR CRYSTALS AND LIQUID CRYSTALS | 1995年 / 262卷
关键词：
D O I：
10.1080/10587259508033530
中图分类号：
O7 [晶体学];
学科分类号：
0702 ; 070205 ; 0703 ; 080501 ;
摘要：
Dielectric relaxation studies are reported of several substances exhibiting the nematic (N) and smectic A (Sm A) polymorphism. From the relaxation times tau(parallel to) characterizing molecular reorientations around the short axes the activation enthalpies Delta H-parallel to for both phases were calculated. It was found that Delta H-parallel to(N) is markedly larger than Delta H-parallel to(SmA). The effect is interpreted on the basis of existing models of Sm A phase.
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页码：257 / 265
页数：9
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