Electron energy bands and the optical properties of potassium iodide and rubidium iodide

Abstract

Using the relativistic mixed basis (M.B.) technique and the non-relativistic O.P.W. technique, electron energy bands are obtained for KI and RbI under a variety of conditions. It is argued that the previous calculations and interpretations offered for the KI optical absorption spectrum are not in agreement with recent experimental results. The present calculation produces results which eliminate the difficulties associated with previous theoretical models, and the results of this calculation are in good agreement with experiment. It is found that the L 1 and X 3 conduction levels play a substantial role in understanding the experimental results. It is also shown that a stringent ‘muffin tin’ potential is a poor approximation to the KI potential. The RbI results are similar to the KI results and a similar experimental interpretation is advanced.