Dimethylsulfoxide - N,N-Dimethylformamide Binary Mixtures and Their Physicochemical Properties

Density and refractive indices for mixtures of dimethylsulfoxide (DMSO) with N.N-dimethylformamide were measured over the whole composition range at 298.15 K, as well as the relative permittivities at 288.15 K, 293.15 K, 298,15 K, 303,15 K and 308.15K. From these data the excess molar volumes, apparent and partial molar volumes of DMSO and DMF, the excess relative permittivity, the temperature coefficients of relative permittivity and Kirkwood's correlation factor for investigated mixtures were calculated. The 1 H-NMR spectra of these liquid binary mixtures, were recorded at 298 K and the spectral parameters, Δδ(DMSO - DMF) were calculated. These structural parameters as functions of concentration suggest the formation of the most stable "complexes" of the 2 DMSO*DMF and DMSO*DMF types.