Autori: Peter Haider, Yuan Chen, Sangyun Lim, Gary L. Haller, Lisa Pfefferle, and Dragos Ciuparu

Editorial: Journal of the American Chemical Society, 127(6), p.1906 -1912, 2005.

Rezumat:

Application of the generalized 2D correlation analysis to a series of in situ XANES spectra enabled the determination of additional useful information not readily available from the conventional spectra. In addition to the changes in the intensity of the white line and in the pre-edge feature, readily observable in the regular spectra, the generalized 2D correlation analysis clearly evidenced an otherwise imperceptible shift in the main edge energy caused by the gradual reduction of Co2+ to metallic cobalt. The 2D correlation spectra also allowed the establishment of a time sequence for the changes occurring in the spectral features during hydrogen reduction, which provides valuable information on the reduction mechanism. While the generalized 2D correlation analysis was found to be very useful in obtaining supplementary information from the series of XANES spectra analyzed, interpretation of the correlation intensities should be checked for consistency with the general trend of each spectral feature, as spectral intensities that do not change monotonically may induce changes in the signs of the correlation intensities leading to inaccurately establishing sequences of changes among the spectral features in the series.

Cuvinte cheie: X-ray absorption spectroscopy, 2D correlation analysis

URL: http://pubs.acs.org/cgi-bin/article.cgi/jacsat/2005/127/i06/pdf/ja045391m.pdf