Luminescence of Crystals of Divalent Tungstates
- Moscow Institute of Steel and Alloys, Leninskii pr. 4, Moscow, 117936 (Russian Federation)
- All-Russia Research Institute for Synthesis of Mineral Raw Materials, ul. Institutskaya 1, Aleksandrov, Vladimir oblast, 601600 (Russian Federation)
- Institute of General Physics, Russian Academy of Sciences, ul. Vavilova 38, Moscow, 119991 (Russian Federation)
Crystals of divalent tungstates are characterized by two main luminescence spectral ranges: a short-wavelength (blue) luminescence band in the range 390-420 nm and a group (often two groups) of longer wavelength (green) bands in the range 480-520 nm. For crystals of calcium, strontium, barium, cadmium, magnesium, zinc, and lead tungstates, it is shown that the wavelength corresponding to the maximum of the blue luminescence band ({lambda}{sub max}) correlates with the melting temperature (T{sub m}) of these compounds. The position of the blue luminescence band is the same (in the range 510-530 nm) for crystals with different divalent cations. Annealing in vacuum and electron irradiation decrease the intensity of both blue and green luminescence bands but do not change the ratio of their maximum intensities. This circumstance suggests that vacancies serve as luminescence quenchers to a greater extent rather than facilitate the formation of emission centers responsible for a particular luminescence band.
- OSTI ID:
- 20666231
- Journal Information:
- Crystallography Reports, Journal Name: Crystallography Reports Journal Issue: 2 Vol. 50; ISSN 1063-7745; ISSN CYSTE3
- Country of Publication:
- United States
- Language:
- English
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