Ligand field and Judd-Ofelt intensity parameters of samarium doped tellurite glass

• Absorption spectra revealed prominent peak in the UV–Vis–NIR region.
• Judd-Ofelt intensity parameters followed Ω4>Ω6>Ω2 trend.
• Quality factor is found to be greater than unity.
• The crystal field strength indicates strong glass structure.
• The values of bonding parameter shows covalent nature.

We report the samarium ions (Sm3+) contents dependent ligand field and Judd-Ofelt (JO) intensity parameters (Ω2, Ω4, Ω6) of zinc tellurite glass. The amorphous nature of the melt-quench synthesized glasses is confirmed using XRD. The lower energy region of the absorption spectra is used to calculate JO intensity parameters and the UV edge is exploited to determine the Nephelauxetic ratio, bonding, and Racah parameters. The Nephelauxetic ratio and Racah parameter is reduced and the bonding parameter is enhanced with the increase of Sm3+ concentration. The enhancement in covalency is found to increase the non-bridging oxygen and crystal field strength by delocalizing more d-shell electrons. Furthermore, Nephelauxetic function revealed an increase due to the reduction of localized d-electrons that is aroused from the overlap of d-orbital and ligand orbital. The JO intensity parameters displayed the Ω4>Ω6>Ω2 trend. Increase in Ω2 and decrease in Ω2 and Ω2 with the increase of Sm3+ concentration indicated an increase in the SmO covalency and coordination in the asymmetry of the prepared glasses. The large vale of spectroscopic quality factor (greater than unity) makes the proposed glass system prospective for various optical devices fabrication.