Orientational order parameter studies in two symmetric dimeric liquid crystals – an optical study

Liquid crystalline material exhibiting multiple phase transitions: morphologic properties and optical transmission

“…Availability of the heterophase regions of SmCSmA phase transition and availability of thermal hysteresis, which were observed in the present work, are a typical display of the first order transition [8, 11, 13, . We would like to emphasize that the heterophase region and the thermic hysteresis for the SmC-SmA phase transition were also observed earlier for compounds with the alkenic terminal group chain in [49].…”

“…Thus, for the abovementioned phase transitions thermal hysteresis takes place. Availability of thermal hysteresis and T* and T** temperatures at the phase transitions in liquid crystals was theoretically predicted in [11,14,38,[40][41][42][43][44][45][46] and was experimentally observed in [47][48][49][50][51][52][53][54][55][56].…”

Orientational order parameter studies on 3.Omand 3O.Omliquid crystals

“…The refractive indices of six 3.Om and 3O.Om (with m D 6À8 in both the cases) LCs are measured using a modified spectrometer [2] and a wedge shaped cell. The temperature accuracy is § 0.1 C. The refractive indices n e and n o are measured at wavelength 589.3 nm.…”

Study of mesomorphism, thermotropic properties and pitch in new chiral smectogenic imine compounds

“…That fact indicates that the thermal hysteresis at phase transitions takes place for LC1-LC4 compounds. The thermal hysteresis for phase transitions has been observed by different scientists in various liquid crystalline materials [48][49][50][51][52][53][54][55][56][57][58]. As is known, availability of the thermal hysteresis in liquid crystals is typical for the first order transitions [1,[59][60][61][62][63][64].…”