Background subtraction from transition metal 2p XPS by deconvolution using ligand atom XPS: Study on first transition metal cyanide complexes

The primary excitation spectra of the first transition metal series 2p X-ray photoelectron spectra for the metal cyanide ions are obtained by a deconvolution method. As the CN^- ions coordinate to the transition metal, N1s spectra are used as a response function for the deconvolution using a Fourier transform method. The obtained spectra have flat zero level backgrounds, whereas the universal curve of the Tougaard method cannot remove the full contribution of energy loss. Among some background subtraction methods, the intensity ratios of 2p_3/2 to 2p_1/2 calculated by the present method are closest to the theoretical photoionization cross section ratios.