On the L‐Bands and the First Exciton Bands in the Photoemission Spectra of Alkali Iodides

The photoemission spectra of NaI, KI, RbI and CsI are investigated experimentally. Besides the bands already revealed by optical absorption measurements and confirmed by photoemission studies, the L1–L4‐bands in Nal, the L4‐band in RbI, and the fine structure of the E1‐bands in KI and RbI are observed. In CsI electron emission is detected corresponding to the first exciton band in the absence of F‐centres. The very intense “extra”‐bands occurring in the absorption spectra are not found.