Prediction of Vapor-Liquid Equilibria Data from C-H Band Shifts of Raman Spectra and Activity Coefficients at Infinite Dilution in Some Aqueous Systems

On the basis of the concept of local composition, a new model is proposed for correlating the Raman frequency shifts of a C-H stretching band over the whole concentration with only one energy parameter. Mixtures investigated include water + acetone, water + 2-propanol, water + N,N-dimethylformamide (DMF), water + methanol, water + ethanol, water + 1,4-dioxane, water + dimethyl sulfoxide (DMSO), and water + acetonitrile systems. The vapor-liquid equilibrium data were predicted by the parameter obtained from the spectra and one activity coefficient at infinite dilution. In this way, the spectroscopic information can be related to thermodynamic properties.