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Intense and broad visible photoluminescent (PL) band in structurally disordered SrWO4 compounds was observed at room temperature. The polycrystalline scheelite strontium tungstate (SrWO4) samples prepared by the polymeric precursor method at different temperatures of annealing were structurally characterized by x-ray diffraction and Fourier transform Raman spectroscopy measurements. Quantum-mechanical calculations showed that the local disorder in the cluster of the network modifiers Sr has a very important role in the charge transfer. The experimental and theoretical results are in good agreement, indicating that the generation of the intense visible PL band can be related to short-range order-disorder degree in the scheelite structure.

An intense and broad visible photoluminescence ͑PL͒ band was observed at room temperature in structurally disordered PbWO 4 thin films. The scheelite lead tungstate ͑PbWO 4 ͒ films prepared by the polymeric precursor method and annealed at different temperatures were structurally characterized by means of x-ray diffraction and atomic force microscopy analysis. Quantum-mechanical calculations showed that the local disorder of the network modifier ͑Pb͒ has a very important role in the charge transfer involved in the green PL emission. The experimental and theoretical results are in good agreement, both indicating that the generation of the intense visible PL band is related to simultaneous structural order and disorder in the scheelite PbWO 4 lattice.

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An intense and broad visible photoluminescence (PL) band was observed at room temperature in short-range disordered BaWO 4 crystals. The scheelite crystalline BaWO 4 powders prepared by the polymeric precursor method and annealed at different temperatures were structurally characterized by means of X-ray diffraction and Fourier transform (FT) Raman spectroscopy measurements. Quantum-mechanical calculations indicated that the disorder at short range only of Ba atoms in the BaWO 4 lattice has a very important role in the charge transfer involved in the intense green PL emission. This indication was detected and confirmed by means of FT Raman spectroscopy measurements. The experimental and theoretical results are in good agreement, both showing the specific type of structural disorder that is the most favorable condition for generating the most intense green PL emission in the scheelite BaWO 4 lattice.