Vibrational Raman spectroscopy of solid benzene-hexafluorobenzene

Using Raman spectroscopy, we have investigated the vibrational spectroscopy and dynamics of both benzene and hexafluorobenzene molecules in solid C6H6:C6F6. We observe both phonon-molecule vibrational interactions and molecule-molecule vibrational coupling. Measurements have been made over a range of sample temperatures, up to the first of a series of solid-state phase transitions, previously, observed in this material. It is seen, that at the temperature of the first phase transition the frequencies of the benzene and hexafluorobenzene intermolecular vibrations approach closely to one another. Our measurements are rationalised with relatively simple molecular models.