Investigations on the Local Structures and the Spin Hamiltonian Parameters for Cu²⁺ in (90–x)TeO₂–10GeO₂–xWO₃ Glasses

Abstract

The local structures and the spin Hamiltonian parameters (SHPs) for Cu2+in (90–x)TeO2–10GeO2–xWO3glasses are theoretically investigated at various WO3concentrations (x=7.5, 15, 22.5 and 30 mol%). Subject to the Jahn-Teller effect, the [CuO6]10−groups are found to experience the small or moderate tetragonal elongation distortions (characterised by the relative tetragonal elongation ratiosρ≈0.35–3.09%) in C4axis. With only three adjusted coefficientsa,bandω, the relevant model parameters (Dq,kandρ) are described by the Fourier type and linear functions, respectively, and the measured concentration dependences of the d–d transition bands and SHPs are reproduced. The maximum ofg∥and the minimum of |A∥| atx=15 mol% are illustrated from the abrupt decrease of the copper–oxygen electron cloud admixtures or covalency and the obvious decline of the copper 3d–3s (4s) orbital admixtures due to the decreasing electron cloud density around oxygen ligands spontaneously bonding with Cu2+and Te4+(W6+), respectively.

Optical and Spectroscopic Features of K2B4O7-Li2B4O7 -TeO2 Glasses Modified with Cu2+ Ions

“…These coloured glasses influence the optical absorption spectra, EPR and structural changes in the glass network. [13][14][15] Chary et al 16 made an effort to test BaF 2 -TeO 2 -Li 2 B 4 O 7 -CuO glasses. The effect of BaF 2 on these glasses were examined using physical and spectroscopic methods.…”