Gorecka E, Nakata M, Mieczkowski J, Takanishi Y, Ishikawa K, Watanabe J, Takezoe H, Eichhorn SH, Swager TM
Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan and Department of Chemistry, Warsaw University, Al.Zwirki I Wigury 101, 02-089 Warsaw, Poland.
Phys Rev Lett. 2000 Sep 18;85(12):2526-9. doi: 10.1103/PhysRevLett.85.2526.
Doping of the ferroelectric Sm-C() phase with bent-shaped molecules induces the antiferroelectric Sm-C()(A) phase. The effect was observed by means of electro-optic and dielectric measurements in systems with weak interlayer interactions in which the relative strength of anticlinic-synclinic order between molecules in adjacent layers is easily controlled by external factors. Fourier-transform infrared spectroscopy studies suggest that the bent-shaped molecules are not flat. They reorient upon the electric field-induced antiferroelectric-ferroelectric transition to adopt a position in which the average direction of the carbonyl groups is in the smectic plane and a bending tip along the C2 symmetry axis.
用弯曲分子掺杂铁电Sm-C（）相可诱导出反铁电Sm-C（）（A）相。在层间相互作用较弱的体系中，通过电光和介电测量观察到了这种效应，在该体系中，相邻层分子间反斜-顺斜有序的相对强度很容易受外部因素控制。傅里叶变换红外光谱研究表明，弯曲分子并非平面状。它们在电场诱导的反铁电-铁电转变时重新取向，以使羰基的平均方向处于近晶平面内，并使弯曲端沿C2对称轴排列。
