Fluorescence and Nonradiative Relaxations of Rare Earths in Amorphous Media and on High Surface Area Supports: A Review

The origins of the electronic levels of rare earths in the condensed phase and the influence of the glassy matrix on the position of the energy levels and factors responsible for radiative and nonradiative transitions are discussed. Examples are given of rare earth intensity parameters and nonradiative transitions in oxide, chalcogenide, and fluoride glasses. The spectral behavior of rare earth ions adsorbed or incorporated into high surface porous materials are discussed.