This project studies the electronic and vibrational excitation, energy-migration, and relaxation processes, involving various molecular and electronic defects in ordered and disordered ionic solids. Research will include electron-vibration energy transfer processes between F-centers and molecular defects will be investigated using resonance Raman scattering, vibrational luminescence and Fourier transform infra-red spectroscopy. A newly developed technique will be used to produce high quality ultra-thin crystals in the range 0.2 - 100 m. The influence of the mesoscopic size on the films on the energy-transfer and phase behavior of the materials will be investigated and may lead to new optical materials or research possibilities. %%% This project involves the study of the optical properties of materials which are typically used in laser devices. One area of interest is that of energy transfer processes that need to be understood in order to optimize the optical and lasing properties of materials. Another important area is that of thin films of optical materials, where the reduced size of the medium changes the properties of crystals in new and incompletely understood ways. The study of these materials may lead to new laser materials or devise applications.