A mesomorphic compound represented by the following formula (I): ##STR1## wherein R.sub.1 and R.sub.2 respectively denote a linear or branched alkyl group having 1-18 carbon atoms capable of including one or two or more non-neighboring methylene groups which can be replaced with ##STR2## wherein X denotes halogen; X.sub.1 and X.sub.2 respectively denote ##STR3## Z.sub.1 denotes ##STR4## A.sub.1 denotes a single bond, ##STR5## and Y.sub.1 and Y.sub.2 respectively denote H, F, Cl, Br, --CH.sub.3 or --CF.sub.3 with the proviso that Y.sub.1 and Y.sub.2 are not simultaneously H. The mesomorphic compound is effective for providing a ferroelectric liquid crystal composition showing an improved low-temperature operation characteristic and a decreased temperature-dependence of response speed.
由以下公式(I)表示的一种中间相化合物:其中R.sub.1和R.sub.2分别表示具有1-18个碳原子的线性或支链烷基基团,可包括一个或两个或更多非相邻亚甲基基团,可用##STR2##替换,其中X表示卤素;X.sub.1和X.sub.2分别表示##STR3## Z.sub.1表示##STR4## A.sub.1表示单键,##STR5##,Y.sub.1和Y.sub.2分别表示H、F、Cl、Br、-CH.sub.3或-CF.sub.3,条件是Y.sub.1和Y.sub.2不同时为H。这种中间相化合物对于提供显示改善的低温操作特性和减少响应速度温度依赖性的
铁电液晶组合物是有效的。