- 著者
- Amano Masakazu Yamamura Yasuhisa Sumita Masato Yasuzuka Syuma Kawaji Hitoshi Atake Tooru Saito Kazuya
- 出版者
- American Institute of Physics
- 雑誌
- The journal of chemical physics (ISSN:00219606)
- 巻号頁・発行日
- vol.130, no.3, pp.034503, 2009-01
- 被引用文献数
- 24 7
The heat capacities of single crystals of organic ferroelectric complexes phenazine-chloranilic acid (Phz-H2ca) and phenazine-bromanilic acid (Phz-H2ba) were measured. At temperatures below those of the reported ferroelectric phase transitions,heat capacity anomalies due to successive phase transitions were found in both complexes. Excess entropies involved in the low-temperature successive phase transitions are much larger than those due to the ferroelectric phase transitions. The temperature dependence of the complex dielectric constants showed the existence of multiple dielectric relaxation modes in both complexes and their deuterated analogs (Phz-D2ca and Phz-D2ba). We discuss the possibility of concerted hopping of neighboring protons within a hydrogen-bonded chain while taking into account the one-dimensional nature of the chain.
- 著者
- Yamaoka Yuuki Taniguchi Yuki Yasuzuka Syuma Yamamura Yasuhisa Saito Kazuya
- 出版者
- American Institute of Physics
- 雑誌
- The journal of chemical physics (ISSN:00219606)
- 巻号頁・発行日
- vol.135, no.4, pp.044705, 2011-07
- 被引用文献数
- 30 12
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.