An infrared study of the interaction-induced vibrational spectra of benzene in liquid binary mixtures containing CS2 and C6F6 Original Research Article

The interaction-induced infrared spectra of benzene (ν9, ν10, ν11 and ν17 bands) have been investigated in liquid mixtures with a range of “solvents”, both polar and non-polar. It has been found that, although some perturbation occurs in all the mixtures, there appear to be much larger excess intensity effects for mixtures with carbon disulphide and hexafluorobenzene. In these two cases the data reflect both the large, expected quadrupole/polarisability electrostatic interactions and the shorter ranged “packing” effects due to average mutual relative orientations in the liquid. The results reported here are consistent with the far infrared data published previously but provide additional information about the vibrational relaxation pathways induced by these weak but significant intermolecular interactions.