Electron spectra from an extensive series of sulfur compounds have been studied. A correlation has been established between the observed position of inner electron lines of sulfur and structure. The influence of structure on the electron binding energies is discussed in terms of a calculated atomic charge, based on the concepts of electronegativity and partial ionic character of bonds. The results are useful for the study of bonding and structure in sulfur chemistry, and are applied particularly to the discussion of the sulfur-oxygen bond (S=O).

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Photoionization cross sections (cr} and photoelectron angular distribution parameters (P} across the (ns', nd') autoionization resonances for Ar, Kr, and Xe have been measured with photon resolu-0 tion widths as low as 0.023 A by means of synchrotron-based photoelectron spectroscopy. The experimental results are compared with those obtained by other experimental techniques and theoretical results. The enhanced resolution allows a redetermination of the width of the ns' resonances.

The Xe 5s,5p photoelectron satellite spectrum has been studied in the photon-energy range from 28 to 75 eV with the aid of synchrotron radiation. This range includes the Xe 5s Cooper minimum, and the cross sections and angular distribution data demonstrate the importance of the strong twoelectron channels in the region where the Ss cross section is small. Although the behavior of the satellites was not recorded over the 4d maximum, the data near 75 eV show an enhancement in the cross section in that region. The data underline the need of including the two-electron channels explicitly in the theory over a wide photon-energy range.

The important dynamic parameters, partial photoionization cross section o. and angular distribution parameter P, have been determined for atomic Mn between 12 and 110 ev by electron spectroscopy with synchrotron radiation (ESSR). The single-electron photolines from the 3d and 4s subshells and the associated two-electron satellite lines were measured, and the resonance region of 3p~3 d excitation around 50 eV was studied in detail. Absolute partial cross sections were derived.For the 3d-subshell properties, we find good agreement with the many-body perturbation-theory calculation (MBPT) by Garvin et al. over the entire energy range and with the random-phaseapproximation results by Amusia et al. over the 3p resonance region. Available calculation (MBPT) underestimates the enhancement of o. (4s) through the 3p resonance. Where overlap exists, the experimental data by Bruhn et al. and by Kobrin et al. agree well with our results. The work on Mn, taken in toto, provides a good overall understanding of the photoionization dynamics of the 3d transition series element Mn, which has a half-filled subshell, although a number of problems, e.g. , twoand three-electron transitions and the low-energy region, remain to be further studied. A need for an accurate determination (5 -10%) of the total photoabsorption cross section is indicated.