Smectic A and C materials with novel director tilt and layer thickness behaviour

We report a smectic liquid crystal in which a tilt of the molecular orienta tion away from the layer normal in the Smectic C phase of up to 24 degrees occurs with minimal layer contraction. This characteristic, accompanied by an exceptionally large underlying negative thermal layer expansion coeffici ent, enables the formation of chiral smectic electro-optical cells having n early the ideal 'bookshelf' layer geometry, free from the complexities of t he chevron layer structure produced by contraction.