The Smetic Polymorphism and the Phase Transitions in the Liquid Crystal 4, n‐Hexyloxyphenyl‐4, n′‐Decyloxybenzoate

Three different methods — microscopical, depolarized light scattering and conoscopic have been used for the investigation of the polymorphism of 4, n‐hexyloxyphenyl‐4, n′‐decyloxybenzoate (HOPDOB) at homeotropic orientation. A new textural transition is registered during cooling in smectic C phase connected with a change in the tilt (ω) and azimuthal (φ) angles of the molecular director. At cooling we found smectic E phase and by the conoscopic method we determined this phase as tilted smectic type (Et) with 24° tilt angle. It is also found that B phase is a normal type smectic liquid crystal — BN.