It is known that W5+, Mo5+, and Fe3+ ions are sensitive indicators for thestructural changes of the local symmetry in oxide glasses. Thus, these centres were used as EPRprobes in P2O5-A(2)MO(4)-A(2)O (M=Mo, W and A=Li, Na). The M5+ ions are located in a distortedenvironment. Their symmetry is lowered as A(2)O content is high. In iron-dopped glasses Fe3+ centresoccupy distorted octahedra. The distortion extent is less than 7%. Radiation-induced defects havebeen detected, it is concerned with a PO42- centre and peroxy radicals.
Boudlich D. Archidi ME. Haddad M. Nadiri A. Berger R. Yahiaoui EM.