Dielectric data, densities, refractive indices, and their deviations of the binary mixtures of N-methyldiethanolamine with sulfolane at temperatures 293.15–328.15 K and atmospheric pressure

Dielectric constants (ɛ), densities (ρ), and refractive indices (nD) were measured for binary blend of tetramethylensulfone (TMS) or sulfolane and N-methyldiethanolamine (MDEA) at temperatures ranging from 293.15 to 328.15 K and atmospheric pressure over the whole mole fraction range. From these experimental data, the excess molar volume (image), and deviations in refractive indices (ΔnD), and relative permittivities (Δɛ), were calculated. These quantities were fitted to the Redlich–Kister polynomial equation to derive the binary adjustable parameters and standard errors. The effective dipole moment of pure liquid was calculated by using of Kirkwood–Frohlich equation.