Research Article
P. Eswarana , R. Ravisankarb a
Abstract
Results on Photoluminescence (PL) studies of KBr1-xI x:TlI (0.01 mol%) mixed crystals grown in vacuum and open air atmosphere are presented in this paper. PL emission spectra of the mixed crystals excited in the A-absorption band of KBr:Tl+ exhibited the characteristic emission bands of Tl+ ions in KBr:Tl+. When excited in the low energy tail of A-band absorption, a broad asymmetrical emission band around 3.64eV with long tail on the low energy side were observed. Comparing with earlier reports, excitation bands observed around 4.8, 4.6 and 4.4eV are attributed to complex thallium centres of the form TlBr6-nIn (n = 0, 1, 2, 3).