Chemical bonding and structure of metastable impurity centers in semiconductor crystals

The properties of metastable impurity centers in semiconductor crystals [II I-V, Il-VI, IV-VI, and II-VII (CdF2)] are considered. Much attention has be en focused on modification of the chemical bond of a regular. crystal in th e presence of doping atoms and on the effect of this modification on the st ructure (including the electronic structure) of the impurity center. Same g eneral consistencies ii? reconstruction of the metastable impurity centers due to variation of their charged state are revealed.