Adsorption effects on the high resolution valence band photoelectron spectra of zinc and cadmium

Photoelectron spectroscopy with 40.81 eV photons has been used to determine accurately the binding energies and spin-orbit splittings of the metallic Zn 3d and Cd 4d electrons. The spin-orbit splittings were found to be 0.65(4) eV and 1.00(5) eV respectively, in good agreement with previously obtained values. The resolution of the doublets was enhanced by deconvolution procedures using an experimentally determined spectrometer line-shape. Clean surfaces of the metals were prepared by mechanical scraping in situ, and the activation energies for adsorption of residual gases on these surfaces have been determined.