Induction of a Ferroelectric S<sub>C</sub>* Liquid Crystal Phase by an Atropisomeric Dopant Derived from 4,4‘-Dihydroxy-2,2‘-dimethyl-6,6‘-dinitrobiphenyl
作者:Kexin Yang、Bryan Campbell、Glenn Birch、Vance E. Williams、Robert P. Lemieux
DOI:10.1021/ja9617505
日期:1996.1.1
We report the induction of a ferroelectric SC* phase in two SC liquid crystal hosts using a novel chiral dopant (−)-1 that incorporates an atropisomeric core derived from 4,4‘-dihydroxy-2,2‘-dimethyl-6,6‘-dinitrobiphenyl. The racemic dopant was synthesized in 11 steps with an overall yield of 9% and resolved by chiral stationary phase HPLC in optically pure form. The magnitude and sign of the spontaneous
我们报告了使用新型手性掺杂剂 (-)-1 在两个 SC 液晶主体中诱导铁电 SC* 相,该掺杂剂包含源自 4,4'-二羟基-2,2'-二甲基-6,6 的阻转异构核'-二硝基联苯。外消旋掺杂剂分 11 步合成,总产率为 9%,并通过手性固定相 HPLC 以旋光纯形式进行拆分。发现由 (-)-1 引起的自发极化 (PS) 的大小和符号强烈依赖于 SC 宿主的性质。在环己烷甲腈主体中,(-)-1 诱导正极化,可在掺杂剂摩尔分数范围 0.02 < xd < 0.044 内测量;在苯甲酸苯酯宿主中,(-)-1 诱导负极化,在 xd ≤ 0.05 时低于检测限。(-)-1 在环己烷甲腈主体中的极化功率 (δp) 为 +170 nC/cm2,这是苯甲酸苯酯主体中估计的上限的八倍多。这些结果是在分子的博尔德模型的基础上合理化的...