DESTRUCTION OF AN INTERCALATED STRUCTURE IN A SMECTIC-A PHASE

The destruction of the intercalated smectic A structure of a laterally bulky branched 1,4-phenylen dibenzoate A by addition of a rodlike cin namate B was studied by the phase diagram as well as by calorimetric, x-ray and dielectric measurements. The thermal stability of the S(A) p hase of compound A and its phase transition enthalpy decrease with inc reasing concentration of B. Furthermore, the destruction of the short range order of A is characterized by increasing layer distances, decre asing dipolar correlation and an increasing dielectric relaxation freq uency only of component A.