Experimental and computational investigation of intermolecular interactions in cyclopentanone with methanol mixture

In this Letter, excess molar volumes, refractive index deviations, Raman spectra and quantum-chemical calculations have been used to explore the underlying intermolecular interactions in the binary mixture containing cyclopentanone (CPN) and methanol. The experimental data reveal that the 1:1 (Ia) and 1:2 (Ib) cross-associations between CPN and methanol are formed in the studied binary mixture. This result has been further corroborated via theoretical calculations. In addition, the observed 1747 and 1732 cm−1 bands can be assigned to the CO stretching vibrations of the intermolecular cross-associations Ia and Ib, respectively, in distinct contradiction with the previous explanations.