Thermodynamic properties of discotic mesogens:: heat capacities and phase transitions of benzene-hexa-n-alkanoates

被引：8

作者：

Asahina, S ^{[1
]}

Sorai, M ^{[1
]}

机构：

[1] Osaka Univ, Res Ctr Mol Thermodynam, Grad Sch Sci, Toyonaka, Osaka 5600043, Japan

来源：

JOURNAL OF CHEMICAL THERMODYNAMICS | 2003年 / 35卷 / 04期

关键词：

heat capacity; phase transition; liquid crystal; discotic mesogen; benzene-hexa-alkanoate;

D O I：

10.1016/S0021-9614(02)00243-4

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

Molar heat capacities of disk-like compounds benzene-hexa-n-nonanoate (BH9) and benzene-hexa-n-decanoate (BH10) have been measured with an adiabatic calorimeter between 13 K and 390 K. Three and two different phases appeared in the solid states of BH9 and BH10, respectively. Molar entropies and transition entropies were determined and compared with those of other benzene-hexa-n-alkanoates BHn (n: 5 to 10). The odd-even effect with respect to the number of carbon atoms in a side chain of a disc-like molecule was observed in the cumulative transition entropies. The molar entropies exhibited a peculiar 'pairing phenomenon' between BH(2m - 1) and BH(2m), where m is integer. This phenomenon is well accounted for in terms of characteristic molecular structure and packing in the crystal lattice. (C) 2003 Elsevier Science Ltd. All rights reserved.

引用

页码：649 / 666

页数：18

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