Separation of double-electron and atomic XAFS contributions in x-ray absorption spectra of Pt foil and Na₂Pt(OH)₆

Abstract

Both double-electron excitation (DEE) and atomic XAFS (AXAFS) contributions are shown to be present in L23 x-ray absorption spectra of Pt foil and Na2Pt(OH)6. In the Fourier transform of the spectra, the DEE feature appears at lower R values than the AXAFS feature. A background subtraction procedure is developed that leaves the DEE contribution in the background and the AXAFS in the oscillatory part of the spectrum. The separation of the DEE and the AXAFS contributions is possible only when using a cubic spline function routine in which the smoothing parameter can be continuously adjusted.