Investigation of intermolecular interactions in binary liquid mixturesof [Bmim][NTf2] and propylene carbonate at different temperaturesusing ultrasonic, optical and FT-IR studies


Speeds of sound and refractive indices of [Bmim][NTf2]þpropylene carbonate mixtures have been measured experimentallyover the entire composition range at 303.15, 308.15, 313.15, 318.15 and 323.15 K, under 101.3 kPa pressure. Semi empiricalrelations of speed of sound and refractive index have been applied for the liquid mixtures in terms of the pure components proposedby different investigators. The deviation of refractive index on volume fraction basisðDfnDÞreported for the binary mixture andfitted using Redlich-Kister polynomial equation. The measured and computed data have been used to interpret intermolecularinteractions between unlike molecules upon mixing. This was further supported by FTIR spectroscopy.