The re-entrant phenomenon in 4'-n-octyloxy-4-cyanobiphenyl: A high pressure X-ray study of the smectic A layer spacing

Abstract

The variation of the smectic A layer spacing of 4'-n- -Octy1oxy-4-cyanobiphenyl (8 OCB) with pressure has been investigated by X-ray diffraction techniques. It is shown for the first time that the occurrence of the re-entrant nematic phase in this compound at high pressures is associated with an expansion of the layer spacing with increasing pressure, confirming the idea proposed originally by Cladis.