Comportement sous pression de smectiques a bicouches

Abstract
The phase diagrams P = f(T) of 4'-n-octyl-4-cyano-biphenyl (OCB) and 4'-n-octyloxy-4-cyanobiphenyl (OOCB), bimolecular smectics A, have been obtained by optical observation of textures in a high pressure cell. The diagram of OOCB shows a domain of existence of the bilayer smectic A ; it is destabilized under pressure for a given temperature