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The electron-spin-resonance $g$ factor for a spin-\textonehalf{} impurity in a dilute alloy is predicted to be logarithmically divergent at low temperatures.

A general theory of the effects of Coulomb excitation of a deep hole state in a solid on the subsequent soft-x-ray emission line shape is given. For excitation energies well above threshold it is shown that the emission corresponds to the decay of a nonrelaxed initial hole state which is suddenly introduced into the solid. Using a weak-coupling approximation, a generalization of the Weisskopf-Wigner formula for radiative line shapes is derived which includes the enhancement of the high-energy tail of an emission line or edge due to initial excitations. Comparison of the approximate results with measurements of the $K$ edge of Li metal provides a reasonable explanation of the observed discrepancy between absorption and emission line shapes.

An argument is given that a model field theory with an $n$-component order parameter has a nonzero critical temperature for large $n$ in two dimensions. A simple dependence of the depression of the $\ensuremath{\lambda}$ point below ${T}_{\ensuremath{\lambda}}$ (bulk) on film thickness is found which correlates with properties of the heat capacity for multilayer He films on graphite observed by Bretz.

Effective-mass corrections due to emission and reabsorption of persistent spin fluctuations are shown to be large in Pd and to have a temperature dependence which fits qualitatively that of the low-temperature specific heat of ${\mathrm{He}}^{3}$.

It is pointed out that the spectra of X-ray induced fast photoelectrons from metal should have a characteristic skew line shape resulting from Kondo-like many-electron interactions of the metallic conduction electrons with the accompanying deep hole in the final state. The same line shape should also occur for the discrete line spectra of X-rays emitted from metals. This mechanism could account for the well-known asymmetries observed for K alpha lines.

The technique of x-ray absorption spectroscopy using tuneable, very intense x-rays from a high energy electron storage ring has been applied to study of the estended x-ray absorption fine structure for Cu and Ni tetraphenylporphyrin and methemoglobin. Preliminary analysis shows that the spectra may be interpreted as a super-position of modulations arising from the nearest neighbor nitrogen and pyrrole alpha-carbon coordination sheels of the metal atoms. We estimate that with the observed magnitude of noise to modulation amplitude, relative shifts of 0,5% in the metal-nitrogen to metal-carbon bond distances in the prophyrins should be observable using extended x-ray absorption fine structure and that this technique may provide a method of observing these types of structural changes in solution.

WE wish to report the first X-ray photoemission spectroscopy (XPS) experiments performed at Stanford Synchrotron Radiation Project, using synchrotron radiation from the Stanford Positron Electron Accelerator Ring (SPEAR) facility. The photoemission technique has been used extensively in the study of the electron properties of materials1,2.