Energies of interaction and other properties of clathrate compounds

Heats of formation of clathrate compounds of β-quinol with argon, oxygen, nitrogen, hydrogen chloride, hydrogen bromide, formic acid and methanol have been determined calorimetrically. For the argon and oxygen compounds, the heats of formation were determined for samples of widely differing composition, and they vary linearly with the fraction of available spaces filled. Using the energy difference between α- and β-quinol obtained directly or by extrapolation of the measurements on the argon and oxygen compounds, the energies of interaction of the enclosed molecules with the β-quinol cage have been determined. Their values are interpreted in terms of the polarizabilities of the enclosed molecules and the number of intermolecular contacts occurring. The free energies of formation, and the colours of the sulphur dioxide and oxygen clathrate compounds are also discussed briefly.