OPTICAL AND ESR-SPECTRA OF THE UV-INDUCED DEFECTS IN THE GLASSES CONTAINING CADMIUM AND ZINC-OXIDES

The photochromic glasses in the CdO-B2O3, CdO-B2O3-SiO2, CdO-SiO2, ZnO-B2O3-SiO2, CdO-Al2O3-SiO2, CdO-Al2O3-B2O3, and ZnO-B2O3 systems are synthesized under the neutral and reducing conditions and studied by the ESR and optical absorption spectroscopy. It is shown that the optical absorption spectra of the irradiated cadmium-containing glasses comprise two bands with peaks at about 20 000 and 27 000 cm(-1). Upon the partial replacement of cadmium by zinc, these bands gradually (but upon the complete replacement, by an abrupt jump) shift toward the peaks at 27 000 and 33 000 cm(-1). The signals from the electron-type defect centers, including signals from the electron delocalized over several Cd ions, are predominant in the ESR spectra of the UV-irradiated cadmium-containing glasses synthesized under the reducing conditions; the high-field Cd+ HFS line is observed (not only after the gamma-irradiation, but after the UV irradiation as well). The signals from the hole-type centers localized on an oxygen dominate in the ESR spectra of the UV-irradiated glasses synthesized under the neutral conditions.