Physico-Chemical Studies on Molecular Interactions of Curcumin with Mono and Divalent Salts at Different Temperature

The ultrasonic velocity, density and refractive indices have been measured for systems at 303.15, 308.15, 313.15, 318.15 and 323.15 K. From the experimental data adiabatic compressibility (βs), intermolecular free length (L f ), internal pressure (π), acoustic impedance (Z), molar refraction (Rm), Polarisability, (αp), thermal expansion coefficient (α), Rao’s molar sound function (R), solvation number (Sn) , Relative Association Parameter (RA) have been computed. Excess properties are fitted to Redlich-kister polynomial equation to obtain binary coefficients and the standard errors with main thrust of the study is to correlate the excess properties and the relevant interactions parameters with the nature of molecular interactions between the mixing components at different temperatures. Lorentz–Lorenz equation and Eykman equations are used to estimate thermal expansion coefficient of the systems from their respective experimental densities and refractive indices. The knowledge of refractive index (n), molar refraction (Rm), thermal expansion coefficient (α) and polarizability (αp) are useful for predicting many physico-chemical properties of solutions.