AN IMPROVED BACKGROUND REMOVAL METHOD FOR XAFS

A new technique for separating the background, mu0, from the XAFS, chi, is presented and shown to be an improvement to standard background removal methods, especially in the near-edge region. The technique optimizes the low-R components of chi(R). For a calculated absorption spectrum for pure Ti, the mu0 found by the presented technique agrees well with the calculated background function. For pure Pb, the extracted mu0 is shown to be nearly the same as that measured from the temperature dependence of the full absorption spectrum starting at an energy in the absorption edge. The reliability of the background from the new method at low-k values allows more information from the XAFS spectra to be used and provides an opportunity for sensitive tests of theoretical calculations in the near-edge region.