Carbon 1s energies are measured by ESCA for a series of aliphatic saturated compounds, carbonyl compounds, and some aromatic compounds. For convenient use in chemical structure analysis the binding energy shifts are correlated with a charge parameter obtained from electronegativity considerations. The shifts are also analyzed in terms of group shifts from which group electronegativities are derived. A comparison is made between the shifts in solid and gaseous samples and it is shown that solid state effects are small for non-ionic compounds. The observed shifts are then compared with results of semi-empirical and ab initio molecular orbital calculations on free molecules. The theoretical calculations are simplified by use of an electrostatic potential model.

The position and shape of the energy bands of the following transition metals have been studied by ESCA: Fe, Co, Ni, Cu, Ru, Rh, Pd, Ag, Os, Ir, Pt, Au. The Fermi levels of the metals with unfilled d-bands are found in the high-energy flanks of the valence band spectra. For the noble metals the Fermi level is shifted toward higher energies. These observations are in general accordance with the overlap of d- and sp-bands in transition metals. An increase in band width is noted between corresponding elements in each series of transition metals. A comparison is drawn between band widths obtained in the present study and those deduced from cohesive energy data. An observed splitting in some of the bands seems to be much too large to be attributable to spin-orbit interaction. Core electron lines are recorded for the purpose of obtaining an energy calibration, estimating the contribution to the observed band spectra from inelastically scattered electrons, and checking the chemical state of the sample. The photoexcitation process and the energy losses of the electrons due to single-particle and plasmon excitations are discussed.

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