is of the best contemplated mode of carrying out the invention this description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense the scope of the invention is best determined by reference to the appended claims the invention provides a liquid crystal compound as shown in formula 1 r is h f cl linear or branched c 1 10 alkyl group linear or branched c 1 10 alkenyl group c 1 10 ether group c 1 10 alkoxyl group linear or branched c 1 10 fluorinated alkyl group linear or branched c 1 10 fluorinated alkenyl group or c 1 10 fluorinated ether group each of a b and c being the same or different is a six member ring such as satured cyclohexyl group unsatured cyclohexenyl group or aromatic benzene ring the carbon of the cyclohexyl group can be replaced by oxygen such as tetrahydropyranyl group or dioxanyl group the carbon of the cyclohexenyl group can be replaced by oxygen such as dioxinyl group the carbon of the phenyl group can be replaced by nitrogen such as pyridinyl group pyridazinyl group or pyrimidinyl group each of l 1 l 2 l 3 l 4 and l 5 being the same or different is h or f z is u2014 c u2550 o o u2014 u2014 oc.