Pretransitional mechanical effects in a smectic-Aliquid crystal

Abstract

Marked pretransition softening is reported of the smectic layer elasticity near the weakly first-order smectic-$A$-nematic phase transition in $N-p-\mathrm{cyanobenzilidene}-p-n-\mathrm{octyloxyaniline}$ (CBOOA). In addition, it is demonstrated that CBOOA will not support a static layer strain. This new relaxation process is studied in detail.