Photoelectric Properties of the Lead Chalcogenides

The energy distribution spectra of electrons photoemitted from the lead chalcogenides by 48.4, 40.8, and 21.2 eV photons have been measured. Both the valence band and the 5d electrons of Pb are observed in these spectra. The valence band portions exhibit considerable structure which is compared with theoretical calculations and with recent X‐rays photoemission work. The d‐electrons spectra are extremely sharp (line width 0.5 eV). They are also compared with theoretical predictions (OPW, KKR, and pseudopotential calculations), with the result of X‐ray photoemission, and with the corresponding spectra of pure Pb. A discussion of the relative intensities of the valence and d‐electron energy distribution spectra is presented.