摘要
通过变温红外光谱对反铁电液晶MHOCPOOB薄膜相变过程中的分子构象、排布及相互作用的变化进行了研究.结果表明,室温时,薄膜中的分子烷基链同时含有zigzag和gauche两种构象.随着温度的升高,有序的zigzag构象转化为无序的gauche构象,链的扭曲程度增加.但S*IA到S*CA的转变并不引起烷基链构象和取向发生明显变化.刚性核中的羰基与相邻的苯环形成共轭体系,苯环之间相互倾斜排列,在相变过程中羰基与苯环的共平面作用逐渐被打破,且在相变点苯环间的二面角明显增大.
The conformation and orientation of the alkyl chain and the core of AFLC were studied by temperature-dependence spectroscopy. The conformation and orientation of the alkyl chain changed obviously as the temperature increased except the phase transition point between the S~*_(IA) and S~*_(CA). Three CO stretching vibrational modes gave two different phase transition behavior. The phase transition between increasing and decreasing temperature was quite different, this is due to the influence of substrate.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第5期931-934,F008,共5页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:20173019
20273022
20375014
20473029)资助
关键词
变温红外光谱
铁电液晶
相变
Temperature-dependent Infrared spectrascopy
Antiferroelectric liquid crystal(AFLC)
Phase transition
