Electronic states spectrum for lead silicate glasses with different short-range order structures

Molecular orbital (MO) linear combination of atomic orbitals (LCAO) simulation of the electronic states spectra of PbOSiO 2 glass with different structures of short-range order is performed. It is determined that superposing of ‘almost free’ Pb 2+ ion levels on silicon-oxygen spectrum takes place in low-lead glass, whereas high-lead glasses are characterized by mixing of Pb and O atoms valency states. Density-of-states peaks in X-ray photoelectron spectra and optical Pb6s → Pb6p transition with 5.2–3.0 eV energy as a function of Pb structural role are identified. The most probable radiation centers in PbOSiO 2 glasses are the analogues of known E − and H + centers formed on the band energies edges as a result of electron-hole localization SiO − … Pb 2+ frgaments.