Induced smectic phase in a nematic liquid crystal mixture

It has been recognized experimentally that a smectic phase can be induced in a nematic mixture via strong mesogenic interaction. To account for an induced smectic phase boundary, we have developed a theoretical model by combining Flory-Huggins (FH) theory for isotropic mixing and Maier-Saupe-McMillan (MSM) theory for ordering of smectic-A phase (Sm-A) in the nematic mixture, although smectic ordering is forbidden in the constituent pure nematic liquid crystals. The predictive capability of the present combined FH-MSM model for the coexistence curves of the nematic mixture and the concomitant induced smectic phase boundary has been critically tested with the reported induced smectic phase diagrams.