Two valence states of tin atoms in (As 2 Se 3 ) 1 -z (SnSe) z -x (GeSe) x and (As 2 Se 3 ) 1 -z (SnSe 2 ) z -x (GeSe 2 ) x glasses are identified by Mössbauer and photoelectron spectroscopy. It is demonstrated that the presence of doubly charged tin ions in the structural glass network does not give rise to impurity conduction or impurity optical absorption. The inference is made that these glasses can be treated as semiconductor solid solutions.

No abstract

No abstract

No abstract

Optical, photoelectronic, and thermal activation methods have been used for studying the forbidden band gap, the energy spectrum of local states in it and the type of electronic transitions, which determine the long-wavelength strong absorption edge in lead oxides (tetragonal ( R o t ) and rhombic (PbO,) mon-