DIELECTRIC RELAXATIONS IN VARIOUS CRYSTAL MODIFICATIONS OF CYCLOHEXANOL AND 2,3-DIMETHYLBUTANE

被引：73

作者：

ADACHI, K

SEKI, S

WADA, Y

SUGA, H

YAMAGUCHI, S

YANO, O

KUBOTA, S

机构：

[1] Department of Chemistry, Faculty of Sciences, Osaka University, Machikaneyama, Toyonaka,560, Japan

[2] Department of Applied Physics, Faculty of Engineering, University of Tokyo, Bunkyo-ku, Tokyo,113, Japan

来源：

MOLECULAR CRYSTALS AND LIQUID CRYSTALS | 1972年 / 18卷 / 3-4期

关键词：

D O I：

10.1080/15421407208083607

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The dielectric constant and loss of crystalline cyclohexanol (CHOL) and 2,3-dimethylbutane (DMB) were measured from 4 K to the melting point, 299 K for CHOL and 145 K for DMB. The supercooled plastic crystal of CHOL above the glass temperature T//g exhibits a prominent relaxation ( alpha ) due to molecular rotation. The temperature dependence of the relaxation time was found to obey the Fogel-Tamman equation. A secondary relaxation ( beta ) was observed below T//g, 149 K for CHOL and 76 K for DMB. The mechanism proposed for beta is internal rotation; rotation of OH bond for CHOL and trans-gauche transformation for DMB. The beta relaxation of DMB is well correlated with acoustic relaxation in the liquid state in the relaxation time versus temperature plot. Relaxations in the intermediate state, crystal III, of these two substances and the most stable state, crystal II of DMB were studied.

引用

页码：345 / +

页数：1

共 25 条

[1] PHASE CHANGES IN CRYSTALLINE AND GLASSY-CRYSTALLINE CYCLOHEXANOL [J].