Abstract: Four pyridine derivative and one simmilar but non-pyridine liquid crystal molecules with two aromatic and one cyclohexane ringed have been examined applying quantum mechanical tools like computational Density Functional Theory, to understand theirelectro-optical and spectroscopic details. The present article reports some liquid crystal moleculesnamely (1). 5-(4-butylcyclohexyl)-2-(4-methoxyphenyl)pyridine, (2). 5-(4-butylcyclohexyl)-2-(3-fluoro-4-methoxyphenyl)pyridine, (3). 5-(4-butylcyclohexyl)-2-(2-fluoro-4-methoxyphenyl)pyridine, (4). 5-(4-pentylcyclohexyl)-2-(4-propylphenyl)pyridine and (5). 1-(4-pentylcyclohexyl)-4-(4-propylphenyl)benzene.having structure of pyridine and its derivative.it was found that differences at micro level will also be responsible for the changes in optical properties like birefringence, dielectric anisotropy, etc. as well as materialistic features like viscosity, elastic constant, etc.

Keywords: pyridine, liqid crystal, density functional theory, electro-optic, spectroscopic.