High-Pressure Investigation of the Reentrant Nematic - Bilayer-Smectic-<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>A</mml:mi></mml:math>Transition

Abstract

We find that certain cyano Schiff bases and cyanobiphenyls with alkyl or alkoxy end groups exhibiting a bilayer smectic-$A$ phase also exhibit a reentrant nematic phase at high pressure. A tentative model of the bilayer smectic phase held in place via the attractive interaction of the alkyl or alkoxy chains accounts for most of our experimental results.