稀土固体发光研究中的几个化学问题

文章综述了近年来在稀土固体发光研究中的几个主要化学问题,着重讨论了化学组成及晶体结构对稀土离子在固态基质中发光的影响。

SOME CHEMICAL PROBLEMS ON LUMINESCENCE STUDIES OF RARE EARTH IONS IN SOLID STATE HOSTS

Some chemical problems on luminescence studies of rare earth ions in solid state hosts are reviewed in this paper.First, the influence of the chemical composition and crystal structure on luminescence properties of rare earth ion activated phosphors is discussed.lt involves the influence of the surroundings of rare earth ion on transition probabilities, luminescence efficiency, thermal quenching and spectral nature.The influence of the surroundings of a rare earth ion on its 4f levels is very weak. This results in a very weak crystal-field splitting of these levels. The transition probabilities for f-f transitions can be strongly influenced by the surroundings. Energy levels and transitions involving a charge transfer or a 5d state are more strongly influenced by the rare earth ion surroundings in the lattice.