ELECTRON-PARAMAGNETIC-RESONANCE AND OPTICAL-ABSORPTION SPECTRA OF FE3+ IONS IN ALKALI CADMIUM BOROSULFATE GLASSES

Electron paramagnetic resonance (EPR) and optical absorption studies h ave been made for Fe3+ ions in alkali cadmium borosulphate [R(2)SO(4)C dSO(4)-B2O3]; R = Li, Na, K or CsI glasses. The Fe3+ EPR spectrum is c haracterized by an intense absorption at g = 4.3 and a broad hump at g = 6.4. The resonance line at g = 4.3 is attributed to Fe3+ ions in an octahedral crystal field and the resonance at g = 6.4 is due to Fe3ions in an axially distorted site. Significant changes have been obser ved in the intensities of the resonance line at g = 4.3 as the Fe3+ io n content is increased in lithium cadmium borosulphate [LiCdBS] glass. The optical absorption spectrum of Fe3+ ions in LiCdBS glass at 300 K shows six bands characteristic of Fe3+ ions in an octahedral symmetry . From the optical absorption spectra the crystal field parameter Dq a nd the Racah interelectronic repulsion parameters B and C have been ev aluated.