文章中考虑了一带有电偶极矩的V形液晶分子系统,假设液晶分子长棒间的简单相互作用以及电偶极矩间的相互作用形式,利用平均场理论,得到含电偶极矩的V形液晶分子系统在电偶极矩间相互作用强度(v0)和温度(t)平面内的相图,以及在V形液晶分子间夹角(α)和温度平面内的三类相图.结果表明,在v0-t平面内的相图曲线中,存在由各向同性相经一级相变直接进入双轴向列相的Landau曲线；而在α-t平面内的第一类相图曲线中,当v0较小时,不存在Landau曲线；在第二类相图中(v0较大时),在合适的电偶极矩相互作用强度和分子间夹角的范围内,系统的相变曲线中才会出现Landau曲线；在第三类相图中(v0最大时),相图特征则与第二类相图相反.
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