Phosphorescence of Benzophenone, Benzophenone-d10, and Decafluorobenzophenone in Rigid Glasses and Crystals under Pressure

The phosphorescence of benzophenone, benzophenone-d10, and decafluorobenzophenone has been studied as a function of pressure (0–30 kbar) at 77°K in nonpolar and polar glasses, as well as from molecules at pressure-induced defect sites in the corresponding crystals. The pressure shift in the triplet spectra is in the order Δ ν F > Δ ν D ≳ Δ νH, while lifetimes are shortened 15%−25% at 30 kbar. The blue shift in hydroxylic glasses and the red shift observed both in hydrocarbon glasses and at crystal defects are rationalized in terms of hydrogen bonding, dielectric interactions, and repulsive interactions, respectively.