2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/151886We propose a Landau-de Gennes phenomenological model to describe the pressure induced smectic A-nematic phase transition. The pressure induced smectic A phase transitions are discussed for varying coupling between orientational and translational order parameter. Increasing the pressure, the first order nematic-smectic A transition becomes second order at a tricritical point which agrees fairly with available experimental results.10 pages, no figure, LaTeX format,e-mail:kisor@juphys.ernet.in, Submitted to Phys. Rev. ESoft Condensed Mattertext