Molecular interaction study through experimental and theoretical volumetric, acoustic and refractive properties of binary liquid mixtures at several temperatures 1. N,N-dimethylaniline with aryl, and alkyl ethers

Abstract

Current study involves the understanding of the thermo-physical properties of N,N-dimethylaniline (DMA) with polar solvents, anisole (ANS) and tert-butyl methyl ether (MTBE). Accurate measurement of density (ρ), speeds of sound (u), viscosity (η) and refractive index (nD) of pure and binary mixtures of DMA with ANS and MTBE at all concentrations and temperatures ranging from 293.15 to 323.15K at 5K interval under atmospheric pressure was used to calculate the thermodynamic properties of the mixtures. Molecular interactions involved in the studied mixtures were explained through Rao's molar sound function (R), deviation in viscosity (Δη) and excess properties such as excess molar volume (VmE), excess molar isentropic compressibilities (Κs,mE), excess free energy of activation of viscous flow (ΔG⁎E) and optical properties such as deviation in refractive index (ΔnD) and deviation in molar refraction (ΔRM). Excess and pure data were fitted to the fourth degree Redlich–Kister polynomial equation. Molecular interactions between the unlike molecules were analyzed through dipole–dipole interaction and charge transfer complex formation in the DMA molecules. Several empirical equations were applied to predict the refractive index and viscosity of the mixtures. Excess molar volumes were fitted through the Prigogine–Flory–Patterson statistical theory and the results were compared with the experimental results.