Fluorescence and Absorption Spectra of Sterically Hindered Arylethylenes in the Neat Glassy State

Abstract

The fluorescence spectra of some sterically hindered arylethylenes in the neat glassy state show a considerable blue shift with respect to those of the crystalline solids, while the absorption is shifted to the red. The small Stokes shift and the reduced half width of the emission band indicate that the emitting excited state is much less relaxed in the glass than in the crystal. The restriction of the relaxation process is discussed in terms of the properties of the disordered glassy state.