THE HEAT-CAPACITY OF THE DOUBLY REENTRANT MESOGEN - 4-CYANOBENZOYLOXY-4'-OCTYLBENZOYLOXY-PARA-PHENYLENE

被引：2

作者：

VANHECKE, GR ^{[1
]}

SORAI, M ^{[1
]}

机构：

[1] HARVEY MUDD COLL,DEPT CHEM,CLAREMONT,CA 91711

来源：

LIQUID CRYSTALS | 1992年 / 12卷 / 03期

关键词：

D O I：

10.1080/02678299208031063

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Heat capacity of a 20 g sample of the mesogen 4-cyanobenzoyloxy-4'-octylbenzoyloxy-p-phenylene was measured in the temperature range 380 to 510 K by adiabatic calorimetry. The C(p) versus T data is interpreted in terms of thermodynamically equivalent S(A1) and S(Ad) phases whose Gibbs potential surface intersects the thermodynamically equivalent reentrant nematic and nematic Gibbs potential surface in such a way as to define the first order doubly reentrant phase sequence: S(A1)-N-S(Ad)-N. The data do not allow any precise estimates of transition enthalpies.

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页码：503 / 513

页数：11

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