Estimation of thermodynamic parameters in 3.Om and 3O.Om liquid crystalline compounds

Thermodynamic parameters such as Moelwyn-Hughes parameter (C1), reduced volume (V~), reduced compressibility (β), isochoric temperature coefficient of internal pressure (X), Sharma parameter (S0), Huggin's parameter (F), Grüneisen parameter (Γp), isothermal microscopic Grüneisen parameter (Γ), fraction free volume (f) and acoustical parameters like isothermal (K′), isobaric (K), isochoric (K″) acoustical parameters, isothermal Grüneisen parameter (Γith), isobaric Grüneisen parameter (Γiba), isochoric Grüneisen parameter (Γich), reduced Bulk modulus (B~), isothermal Anderson-Grüneisen parameter (δ) and magnitude of repulsive exponent (n) are estimated from thermal expansion coefficient, α obtained from density variation with temperature, ρ in liquid crystalline N-(p-n-propyl/propyloxybenzylidene)-p-n-alkoxy anilines, 3.Om and 3O.Om with m = 6, 7 and 8. In addition to these, the parameters like molecular free length (Lf), molecular radius (mr) and nonlinearity parameter, (B/A) are also evaluated. The variation of all these parameters are studied both with the temperature in an individual compound and with the chain length in a homologous series. Further, the results agree with the body of the data available.