分子双轴性与向列型液晶在各向同性相的最低过冷温度

MOLECULAR BIAXIALITY AND THE LOWEST SUPERCOO LING TEMPERATURE FOR NEMATIC LIQUID CRYSTALS IN ISOTROPIC PHASE

在分子场近似下，研究分子双轴性对向列型液晶在各向同性相最低过冷温度Ｔ的影响．理论结果表明，通过考虑分子双轴性，各向同性相最低过冷温度Ｔ与向列相—各向同性相相变温度Ｔｃ的比值向实验值靠近．当分子双轴性参数δ取到０３时，Ｔ／Ｔｃ达到０９８１７，已很接近０９９的实验值．

Abstract In the molecular field approximation, we study the effect of molecular biaxiality on the lowest supercooling temperature of nematic liquid crystals in isotropic phase. Theoretical results show that by taking into account the molecular biaxiality, the ratio of the lowest supercooling temperature in isotropic phase T * to the nematic isotropic phase transition temperature T c, approaches the experimental value. When the molecular biaxiality parameter δ reaches 0.3, the ratio T */T c reaches 0 9817, very close to the experimental value of 0.99.