On the UV Absorption of Heavy Metal Ions in Alkali Halide Crystals I. Experimental Results

Abstract UV absorption spectra of Ag + , Cu + , and Tl + centres in alkali halide crystals are measured between 5 and 300°K in order to determine the electronic fine structure of the bands as well as the magnitude and temperature dependence of the UV dipole strength. The structure and temperature dependence of the spectra are interpreted in terms of electron—phonon interaction and off‐centre effects.