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A new series of Sm 3+ doped borophosphate glasses 50B 2 O 3 + 20Li 2 CO 3 + 10ZnO + 9SrCO 3 + (11 − x )P 2 O 5 + x Sm 2 O 3 ( x = 0.1, 0.25, 0.5, 1 and 2 in wt%) have been prepared by following melt quenching technique. The structural and optical properties of the prepared glasses were characterized through XRD, FTIR, absorption, luminescence and decay spectral measurements. The XRD spectrum exhibit broad diffusion at lower angles which reveal the amorphous nature and the presence of various functional groups such as P O P bonds, B O vibrations in BO 3 units and P OH and B OH bonds in the title glasses were confirmed through the FTIR spectra. The nature of the metal–ligand bonding and the electronic band structure has been investigated using the absorption spectra. The Judd–Ofelt (JO) intensity parameters ( Ω 2 , Ω 4 and Ω 6 ) were evaluated from the JO theory using the refractive index and the experimental oscillator strength values. The emission spectra exhibit four emission bands in the visible region corresponding to the 4 G 5/2 → 6 H 5/2 , 4 G 5/2 → 6 H 7/2 , 4 G 5/2 → 6 H 9/2 and 4 G 5/2 → 6 H 11/2 transitions by monitoring an excitation wavelength at 403 nm. The emission spectra have been characterized through Commission International de I’Eclairage (CIE) 1931 chromaticity diagram to explore the dominant emission from the studied glasses. The radiative parameters such as transition probability ( A R ), branching ratios ( β R ) and stimulated emission cross-section ( σ P E ) were obtained for the emission transitions using JO parameters and the results were discussed and compared with the reported literature. [ABSTRACT FROM AUTHOR]

Abstract: Single crystal EPR, optical, FT-IR and powder XRD studies of VO(II) ion doped diaqua(2,2′-bipyridine) malonato zinc complex were carried out at room temperature to ascertain the structural properties. In EPR, the angular variation of vanadium hyperfine lines indicated a single site, with spin Hamiltonian parameters as: gxx =1.968, gyy =1.964, gzz =1.928, Axx =7.54mT, Ayy =6.36mT and Azz =18.81mT. In addition, the dopant had entered the lattice in an interstitial position and the position had been identified with the help of atom positions of the host lattice. The EPR and optical data was corroborated to obtain various bonding parameters, from which the nature of the bonding in the complex was discussed. FT-IR and powder XRD studies were used to observe the effect of dopant on structural parameters of the host lattice. [Copyright &y& Elsevier]

Abstract: Optical and EPR investigations of chromium and nickel doped zinc phosphate glasses are carried out at room temperature to evaluate crystal field, spin-Hamiltonian and bonding parameters. For Cr3+ ion, the site symmetry is ascribed to a distorted octahedron, whereas the Ni2+ ion is located in a near octahedral site. In addition, the bonding parameters suggest covalent nature for Cr3+ and a moderate covalent nature for Ni2+ in the zinc phosphate glasses. [Copyright &y& Elsevier]