CORE-VALENCE LUMINESCENCE IN DISORDERED LITHIUM-CESIUM CHLORIDE

Luminescence properties of lithium-cesium chloride compounds have been studied using X-rays and synchrotron radiation. In addition to long-l ived luminescence bands, attributed to radiative decay of self-trapped excitons (STE) and defect centers, a fast wide-band emission peaking at 4.4 eV is found to appear under excitation by photons with an energ y above 14.1 eV. This band is ascribed to core-valence luminescence (C VL) caused by radiative recombination of electrons from the 3pCl valen ce band and 5pCs core holes. The peculiarities of the CVL excitation s pectrum and, the shape of the emission spectrum are briefly discussed. (C) 1998 Elsevier Science B.V. All rights reserved.