Non-coincidence effect study of NN-Dibutyl formamide in binary liquid mixtures

Abstract

Abstract The isotropic and anisotropic Raman peak frequency of C O stretching mode of N, N Dibutyl formamide (DBF) have been studied in Dimethyl Sulfoxide (DMSO) and Chlorobenzene (CLB) solvents. The shift of peak wavenumber with the increase in solute concentration has been studied. Hydrogen bonding and the difference in dielectric constant may be responsible for shifting the peak positions. The non-coincidence effect (NCE) has been studied for the CLB and DMSO solvents. The optimized geometrical structures of DBF, DBF-DMSO and DBF-CLB are determined. The peak wavenumbers of the neat solute and in binary mixtures are compared and are found consistent with the theoretical data. The relative splittings ∆ υ ∆ υ neat of the C O stretching mode of DBF for the neat liquid and in solution are determined and have been compared with three theoretical models such as Mc Hale's model, Mirone's model and Logan's model, respectively. The data obtained through theoretical models were almost consistent with the experimental data.