Volumetric, refractive and FT-IR behaviour of β-pinene with o, m, p-cresol at 303.15, 308.15 and 313.15 K

Density (p) and refractive index (no) of binary mixtures of beta-pinene with o, m, p-cresol have been measured over the entire composition range expressed by mole fraction (x(1)) and volume fraction (phi(1)) of the beta-pinene at 303.15, 308.15 and 313.15 K at atmospheric pressure. The FT-IR measurements were carried out at 298.15 K. From the experimental data, excess molar volume (V-E), deviation in refractive index (Delta n(D)) and deviation in molar refraction (Delta R-m) have been calculated and fitted to the Redlich-Kister polynomial equation. The excess or deviation parameters were plotted against mole fraction or volume fraction of the beta-pinene over whole composition range. The observed negative or positive values of excess or deviation parameters were explained on the basis of the intermolecular interactions present in these mixtures. A comparative study of mixing rules namely Arago-Biot, Dale-Gladstone, Lorentz-Lorenz, Eykeman, Weiner, Heller, Newton, Oster and Eyring-John has been carried out to test their validity for these binaries over entire mole fraction of beta-pinene at three temperatures. Comparison of various mixing rules has been expressed in terms of average deviation. The FT-IR study reveals that complex formation becomes maximum at 0.3 mole fraction of beta-pinene, which is also supported by the V-E and Delta n(D) data. The position and pattern of intensity of -OH bands as per FT-IR data strongly supports the conclusion that molecular association through H-bonding has taken place. 2013 Elsevier B.V. All rights reserved.