Molecular interactions in the binary solutions of methyl cellosolve with chlorobenzene: Spectroscopic and dielectric studies

Abstract

H-bond interactions of methyl cellosolve (MCS) with chlorobenzene (CBZ) have been studied using FTIR spectroscopy and Time Domain Reflectometry (TDR) studies. (MCS)O−H⋯π(CBZ) , (MCS)O−H⋯Cl(CBZ) , (MCSCH2)C−H⋯π(CBZ), (MCSCH2)C−H⋯Cl(CBZ) H-bond interactions may exist in the MCS-CBZ binary solutions. The shifts in the ν(C−O−C) and ν(C−OH) stretching bands on mixing are due to the proximity effect arising out of the involvement of both CH2 and O−H hydrogens, respectively, in heteromolecular H-bond. The role of molecular interactions and molar volumes become relatively less significant in determining the relaxation times of the solutions. Instead, the viscosity plays a more dominant role in determining the relaxation times of the MCS-CBZ solutions. Parallel orientation of dipoles is favoured in MCS rich solutions while in CBZ rich solutions the dipoles prefer antiparallel alignment. The excess values of the dielectric constant and free energy show negative and positive deviations, respectively.