胆甾相液晶的相诱导双轴性

采用胆甾相液晶的格胞理论，运用一定的统计方法，导出分布函数，定义序参数张量，由此推导出自由能表达式．在定域坐标系中，对胆甾相的长程取向序参数Ｓ和相诱导双轴序参数Δ进行了数值计算．所得的结果较前人有了不同程度的改善，和实验接近关键词：

PHASE-INDUCED BIAXIALITY IN CHOLESTERIC LIQUID CRYSTALS

The liquid cell theory can be successfully applied to cholesteric liquid crystals. Using the statistical methods and defining an order parameter tensor　 we ded uce the distribution function and the Helmholtz free energy　 which is the functi on of the order parameter tensor and its derivatives. The expression of the free e nergy we obtain has the same form with of the Landau theory. In a local coordina te system　the long－range orientational parameter Sand the phase－induced biaxiality order parameter are defined. By minimizing the Hemholtz free energy　 we numerically calculate the temperature dependence of Sand .The r esults agree with the experiment.