Structure and Formation Mechanism of Ge Related Paramagnetic Centers in Ge-Doped Silica Glass (SOLID STATE CHEMISTRY-Amorphous Materials)

Abstract

We have performed ab initio quantum chemical calculations on clusters of atoms modeling a divalent Ge defect in Ge-doped SiO2 glasses. It has been found that the divalent Ge defect interacts with a nearby GeO4 tetrahedron, forming complex structural units that are responsible for the observed photoabsorption band at ~ 5eV. We have shown that these structural units can be transformed into two equivalent Ge E’ centers by way of the positively charged defect center.