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Strontium-aluminium-bismuth-borate glasses (SAlBiB) doped with different concentrations of Ho(3+) were prepared using conventional melt quenching technique and their structural and optical properties investigated. X-ray diffraction and scanning electron microscopy analysis were used to study the structural properties. Optical properties were studied by measuring the optical absorption and visible luminescence spectra. The Judd-Ofelt (J-O) theory was applied to evaluate J-O intensity parameters, Ω(λ) (λ = 2, 4 and 6). Using J-O intensity parameters, radiative properties such as spontaneous transition probabilities (A(R)), branching ratios (β(R)) and radiative lifetimes (τ(R)) were determined. From the emission spectra, a strong green emission nearly at 549 nm corresponding to the transition, (5)S2 ((5)F4)→(5)I(8) was observed. Emission peak positions (λ(P)), effective bandwidths (Δλ(eff)) and stimulated emission cross-sections (σ(p)) were calculated for the observed emission transitions, (5)F3 →(5)I(8), (5)S2((5)F4)→(5)I(8) and (5)F5 →(5)I(8) of Ho(3+) in all the glass matrices. Chromaticity color coordinates were calculated using the emission spectra. The experimental results suggest that SAlBiB glass matrix with 1.5 mol% of Ho(3+) has better emission properties.

Monophasic PbMoO 4 possessing tetragonal symmetry with varied Eu 3? concentrations is synthesized by solid state reaction method. The samples are characterized by X-ray diffraction, scanning election microscope, energy dispersive spectra, excitation spectra, emission spectra and decay curves. Single cubic phase of PbMoO 4 crystal is confirmed by X-ray diffraction analysis. Analysis of the photoluminescence spectra indicates that the phosphor can be excited by UV light of 386 nm, thus emitting intense red light. The ratio of red emission ( 5 D 0 ? 7 F 2 ) to orange emission ( 5 D 0 ? 7 F 1 ) is very high in present phosphor. This may be due to a lower symmetry of crystal field around Eu 3? ions. The color coordinates are calculated for PbMoO 4 :Eu 3? phosphor located in International Commission on Illumination chromaticity diagram.