EFFECT OF MOLECULAR-STRUCTURE ON THE PHASE-BEHAVIOR OF SOME LIQUID-CRYSTALLINE COMPOUNDS AND THEIR BINARY-MIXTURES IV - DEPENDENCE OF T-C ON THE ANISOTROPY OF POLARIZABILITY OF THE ARYL-X BOND

Transition temperatures of binary mixtures of the two series, 4-hexade cyloxyphenyl-4'-substituted benzoates (Ia-d) and 4-substituted phenyl- 4'-hexadecyIoxybenzoates (IIa-d), have been determined on cooling and the phase diagrams compared with those previously obtained on heating. T-c values for the monotropes and the non-LC analogues have been eval uated by extrapolation. Examination of both series revealed that the s quare root of T-c is related to the polarizability anisotropy, Delta a lpha(X), of the C-Ar-X bond, except for the methoxy derivatives.