磁场作用下向列型液晶中的分子取向短程关联

从分子统计理论的观点研究磁场对向列型液晶的作用。将向列型液晶的格胞理论推广到包含磁场作用的情况。这一理论考虑了分子取向短程关联。向列相序参数对约化温度的依赖关系和每个分子的约化内能对约化温度的依赖关系，与计算机模拟结果符合得相当好。计算了各向同性相最低过冷温度，理论结果与实验值和分子场理论的结果进行了比较。

THE SHORT RANGE CORRELATIONS OF MOLECULAR ORIENTATIONS IN NEMATIC LIQUID CRYSTALS WITH MAGNETIC FIELDS

The effects of magnetic fields applied to nematic liquid crystals are stuided from the point of view of the molecular statistical theory. The cell theory of nematic liquid crystals is extended to the case in the presence of a magnetic field. The theory takes account of the short range correlations of molecular orientations. The dependence of the nematic order parameter on the scaled temperature and the dependence of the scaled internal energy per molecule on the scaled temperature, are fairly good agreement with those of the computer simulation. The maximum supercooling temperature of the isotropic phase is calculated and the theoretical result is compared with the experimental value and that of the molecular field theorry, We concluded that short range correlations of molecular orientations are important for nematic liquid crystals with magnetic fields.