Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan.
J Chem Phys. 2011 Jul 28;135(4):044705. doi: 10.1063/1.3615491.
Quasi-binary (QB) picture of thermotropics, which regards a neat thermotropic liquid crystal as a binary system consisting of (semi)rigid core and molten alkyl chain, was assessed experimentally for the most famous (and representative) thermotropic mesogenic series nCB. By adding n-heptane as solvent, the smectic A phase was induced in 7CB-n-heptane system. Small angle x-ray diffraction showed that the QB picture holds not only in the phase behavior but also in the structure. It is suggested that the melting of 8CB and 9CB to isotropic liquid via smectic and nematic liquid crystals can be understood as a thermotropic-lyotropic crossover.
拟二元（QB）图谱法研究向列型热致液晶，即将规整的热致液晶视为由（半）刚性核和熔融烷链组成的二元体系，已被实验评估用于最著名的（和有代表性的）热致介晶系列 nCB。通过添加正庚烷作为溶剂，在 7CB-正庚烷体系中诱导出近晶 A 相。小角 X 射线衍射表明，QB 图谱不仅在相行为中，而且在结构中都成立。建议通过近晶相和向列相液晶将 8CB 和 9CB 熔融为各向同性液体可以理解为热致-溶致交叉。
