Solid solutions of aromatics in n-paraffins (the schpolskii effect) - I. Isolated molecules in fast frozen samples

The sites in which coronene, 1,12 benzoperylene or perylene are trapped in fast frozen n-paraffin matrices from n-hexane to n-nonane have been determined by careful examination and comparisons between their electronic spectra under especially well defined conditions of preparation and observation. Two types of sites are defined: substitutional sites, and "pseudo-liquid" sites. The differences observed between their thermal and spectroscopic properties are analyzed and explained. The steric and kinetic conditions of formation of these sites arc discussed.