Photoelectric Emission from KCl in the Photon Energy Region from 1.0 to 6.0 eV

Abstract

Photoemission was observed from shallower levels than the valence band maximum. This supports the model that surface levels exist in the band gap and electrons are emitted from these levels. On the whole, the yield curve of pure KCl is divided into two parts: small yields below 4.0 eV and a structured exponential rise above 4.0 eV. From this, the Fermi level of the surface is estimated to be situated 4.0 eV below the vacuum level. The exponential rise is modified by structures such as shoulder and dip. Compared with the curve of pure KCl, the yield curve of coloured KCl suggests that the photoemission reflects surface rather than bulk properties.