Optical and FT Infrared spectral studies of vanadium ions in cadmium borate glass and effects of gamma irradiation

Abstract Combined optical and infrared absorption spectra of V 2 O 5 -doped cadmium borate glasses were investigated before and after gamma irradiation with a dose of 8 Mrad (=8 × 10 4 Gy). The undoped base cadmium borate glass reveals a spectrum consisting of strong charge transfer UV absorption bands which are related to the presence of unavoidable contaminated trace iron impurities (mainly Fe 3+ ). The V 2 O 5 -doped glasses reveal an extra band at 380 nm and the high V 2 O 5 -content glass also shows a further band at about 420 nm. The observed optical spectrum indicates the presence of vanadium ions mainly in the pentavalent state (d 0 configuration). The surplus band at 420 nm shows that some trivalent vanadium ions are identified at high V 2 O 5 content. The optical spectra of the glasses after gamma irradiation show small decrease of the intensity of the UV absorption which are interpreted by assuming the transformation of some Fe 3+ ions by photochemical reactions with the presence of high content (45 mol%) of heavy massive CdO causing some shielding behavior. FT infrared absorption spectra of the glasses show vibrational bands due to collective presence of triangular and tetrahedral borate groups in their specific wavenumbers. The FTIR spectra are observed to be slightly affected by both the V 2 O 5 -dopants being present in modifying low percent or gamma irradiation due to the presence of high content heavy CdO.