Effect of density variation on the Sm A–I phase transition properties. (3rd June 2019)

• Record Type: Journal Article
• Authors: Kumari, Sunita; Singh, Shri
• Is Part Of: Phase transitions. Volume 92:Number 6(2019)
• Page Start: 571
• Page End: 580
• Publication Date: 2019-06-03
• Subjects: Liquid crystal -- thermodynamic properties -- phase transition -- Landau coefficients -- free energy equation; Phase transformations (Statistical physics) -- Periodicals; 530.47405
• DOI: 10.1080/01411594.2019.1607344
• Languages: English
• ISSNs: 0141-1594

Abstract

ABSTRACT: Based on a thermodynamic model, we investigate how the density variation influences the smectic (Sm A)–isotropic (I) phase transition. We find that the density variation shifts the smectic A–isotropic transition temperature, however, first-order nature of the transition remains the same. Here, we also examine the effect of high pressure on the thermodynamic quantities. The present analysis shows that the pressure strongly influences the enthalpy and density step at the clearing transition. The pressure dependence of the thermodynamic properties is incorporated through the pressure dependent second Landau coefficient and the coefficients which couple the nematic and smectic order parameters to the density. We find a close agreement between theoretical and experimental results. Furthermore, we discuss the implications of the results for achiral liquid crystals.