Electron spin resonance and optical absorption spectra of Cr 3+ and Cu 2+ ions in K 2SO 4ZnSO 4 glasses

Abstract

ESR and optical absorption of Cr 3+ and Cu 2+ ions doped in K 2SO 4ZnSO 4 glasses have been studied at different temperatures (123 K to 423 K). Changes have been observed in the spectrum with changes in temperature, concentration and composition of the glasses. The low field spectral line of the ESR spectrum of Cr 3+ ions in K 2SO 4ZnSO 4 glasses is attributed to isolated Cr 3+ ions whereas the high field spectral line is assigned to exchange coupled pairs of Cr 3+ ions. ESR spectrum of Cu 2+ ions doped glasses exhibit a pronounced peak at g = 2.06, and a quadruplet at g = 2.41, the latter arising from the hyperfine splitting of g V; . From the optical absorption spectrum of Cr 3+ ions doped glass, the crystal field parameter ( Dq) and the Racah interelectronic repulsion parameters ( B and C) have been evaluated. The optical absorption spectrum of Cu 2+ ion doped glass shows a broad absorption band which is attributed to the 2 B 1 g → 2 B 2 g transition. By correlating the ESR and optical absorption data, the bonding orbital coefficients α 2 and ß 2 1 for Cu 2+ ions have been evaluated.