Dr. P. Glatzel (European Synchrotron Radiation Facility (ESRF), Grenoble, France) and his colleagues recently published an interesting paper reporting systematic studies on both X-ray absorption and Kα emission spectra from sulfur compounds. The compounds' spectra were compared with quantum chemical calculations using density functional, multiple-scattering, and atomic multiplet theory. It was found that the near-edge absorption spectra are mainly determined by the geometry of the first coordination sphere in the case of the sulfates and sulfite, while strong orbital hybridization in the case of sulfides results in a much more complex analysis. On the other hand, the spectral shape of the Kα fluorescence lines shows little influence of the chemical environment, but its energy position is correlated with the valence-shell electron population. The experiments were done at beamline ID26, ESRF. The spectrometer used for Kα emission is a combination of a Johansson Si(111) crystal and a CCD camera. The energy resolution was 0.44 eV for S Kα. For more information, see the paper, "Electronic Structure of Sulfur Studied by X-ray Absorption and Emission Spectroscopy", R. A. Mori et al., Anal. Chem., Article ASAP, DOI: 10.1021/ac900970z
