On the Luminescence of Ba5M4O15(M=Ta5+, Nb5+)

✍ Scribed by A.M. Srivastava; J.F. Ackerman; W.W. Beers

• Book ID: 102604176
• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 236 KB
• Volume: 134
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1997.7574

✦ Synopsis

The low-temperature luminescence properties of the perovskite-derived materials, Ba 5 M 4 O 15 (M ‫؍‬ Ta 5؉ , Nb 5؉ ) are reported and discussed. The octahedrally coordinated tantalate groups of Ba 5 Ta 4 O 15 exhibit a blue emission, whereas the niobate groups in Ba 5 Nb 4 O 15 luminesce yellow upon excitation with short wavelength ultraviolet radiation. The low quenching temperatures of the tantalate and niobate luminescence are a result of energy migration to quenching sites in the host lattice. The luminescence characteristics of Ba 5 Ta 4 O 15 and Ba 5 Nb 4 O 15 are compared with those reported for other perovskite-based tantalates/niobates and the results are discussed in terms of electronic delocalization of the excited nd 0 configuration.