Cu2+ ions in sodium fluoride-sodium borate glasses studied by EPR and optical absorption techniques

摘要: Electron paramagnetic resonance (EPR) and optical absorption spectra of Cu2+ ions in 80Na2B4O7-(20 − x)NaF xCuO (NFNB) glass system with 0 ≤ x 6 mol% have been studied. EPR all the samples exhibit signals characteristic ions. The values spin-Hamiltonian parameters indicate that sodium fluoride-sodium borate glasses were present octahedral sites tetragonal distortion. number spins (N) participating was calculated as a function temperature for NFNB sample containing 1 activation energy calculated. From data, susceptibility (χ) at various temperatures Curie constant from 1/χ T graph. these show broad band centered 13280 cm−1 which is assigned to 2 B 1g → 2 B 2g transition distorted sites. gap (E opt) Urbach (ΔE) are their ultraviolet edges. It observed copper ion concentration increases, E opt decreases while ΔE increases. This has explained due creation additional localized states by CuO, overlap extend mobility matrix. By correlating molecular orbital coefficients evaluated.