UV-visible emission of (O2- - F+) centres in KBr

✍ Scribed by F. Zehani; M. Sebais

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 101 KB
• Volume: 42
• Category: Article
• ISSN: 0232-1300
• DOI: 10.1002/crat.200710973

✦ Synopsis

Abstract

Single crystals of KBr containing the (O^2‐^ ‐ F^+^) color centres and elaborated in atmospheric air by the Czochralski method are studied. The measure of the UV‐visible emission spectra at 78 K present several emission bands situated between 340 and 800 nm. The photoluminescence excitation shows that these emissions are attributed to O^‐^~2~ and (O^2‐^ ‐ F^+^) centres. This study show the new emission bands of (O^2‐^ ‐ F^+^) centres which are situated in the UV‐visible spectral domain. The comparison between the emission spectra before and after the thermal treatment of samples shows clearly the transformation of O^‐^~2~ centers at high temperature to (O^2‐^ ‐ F^+^) centres. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)