Influence of tetraalkylammonium chain length cation on molecular interactions of dioxane-DMSO-H2O mixtures using ultrasonic technique at various temperatures

Abstract

Thermophysical properties provide a deep and meaningful picture of various interactions taking place in ternary and higher component liquid mixtures. Density (ρ), viscosity (η), and ultrasonic velocity (u) have been determined for the ternary liquid mixture of 1,4-dioxane-DMSO-water of different percentage compositions in the presence of quaternary alkyl ammonium iodide salts (R₄NI) of varying alkyl chain lengths at 303.15, 313.15 and 323.15 K. From the experimental data, the acoustical parameters such as adiabatic compressibility (β_ad), intermolecular free length (L_f), free volume (V_f), acoustic impedance (Z) and relaxation time (τ) have been evaluated. Studies at different temperatures have been carried out to check the validity of Frank’s hypothesis as well as Eyring and Kincaid theory of model of propagation of sound velocity due to weak complex formation because of hydrogen bonds. The present investigation involves the study of nature of molecular interactions, molecular rearrangement and hydrogen bond making/breaking phenomena.