Luminescence behaviour of Eu2+-doped BaClI and BaBrI

BaCII and BaBrI were prepared by the solid-state reaction method. For these two newly prepared compounds, from their high resolution powder X-ray diffraction (XRD) patterns, it is possible to assign them an orthorhombic structure. Interest in these compounds also stems from their application in X-ray screen intensifiers. Europium-doped BaCII and BaBrI were taken up for luminescence studies. The photoluminescence (PL) spectra of both these phosphors showed broad emission bands centered around 410 nm. Their excitation spectra showed two peaks at 270 and 360 nm, respectively. X-ray excited optical luminescence (XEOL) observations and thermo-stimulated luminescence (TSL) measurements were also made on these materials. A noteworthy feature was that unlike BaBrI, BaCII showed a persistence of glow even after removal from the X-ray beam. (C) 2002 Published by Elsevier Science B.V.