Abstract
By heat pulse experiments it is demonstrated that selectively narrow-band laser-excited perylene, matrix-isolated in Langmuir films provides a memory for detecting high-frequency acoustical phonons. This phonon memory, the phonon-modulated fluorescence spectrum, and Debye-Waller factor variations can be explained by the electron-phonon interaction, statistically distributed dye sites, and a model in which dye-site changes in noncrystalline matrices, containing two-level configurations, are induced by phonons and photons.