Benzoate esters homologous series of liquid crystals [LC] is synthesized and studied, with a view to understand and establish the relation between molecular structure and liquid crystal behavior. Totally nine homologues, viz; Methyl to hexyl, octyl, decyl and dodecyl derivatives of the series are synthesized. Methyl and propyl derivatives of the series are nonmesomorphic, while, rest of the homologue derivatives are monotropically or enantiotropically mesomorphic. All the mesomorphic homologues exhibit nematogenic charavter except decyl and dodecyl homologues. Smectic mesophase commences from octyl derivative. Clear cut odd-even effect is not observed for nematic-isotropic transition ( or vice versa ) curve in a phase diagram plot. Solid-isotropic or nematic transition curve and smectic- nematic or isotropic transition curves behaves in normal manner. Series is predominantly nematogenic and partly smectogenic. Nematogenic mesophase is of threaded or schlieren texture and that of smectic mesophase is focalconic fan shaped of Sm-A type as determined from hot stage polarizing microscope. Analytical data support the structure of molecules. Mesomorphic properties are compared with structurally similar series.
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