摘要
手性反铁电液晶分子中的各个不同片段、不同基团在电场诱导下展现不同的取向与取向分布。在交变电场的作用下 ,分子中各个部分的翻转动力学行为也表现的不同。
We employed dynamic and polarized infrared spectroscopy to monitor the response of different molecular segments to external electric fields.Measurements of absorbance changes of the representative IR bands as a function of the polarization rotaion angle at 109 ℃ under DC electric fields of 0,15 and -15 V determine mutual arrangement of different molecular segments in their equilibrium state in the helicoidal Sm C A phase (0 V) and field induced,unbound Sm C phase (15 and -15 V).It is clear from the normalized absorbance changes d A n vs wave electric field at 5 KHz repetition rate that the different segments complete the reorientation at different time scales.The core moves faster and takes ～33 μs to complete the reorientation,while it takes ～64 μs for the alkyl chains and the C=O group.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2000年第5期598-600,共3页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金!重点项目 ( 96330 1 0 )资助课题
关键词
偏振红外光谱
手性反铁电液晶
翻转动力学
Polarized infrared spectroscopy
Time resolution
External electric fields
