Static exchange and cluster modeling of core electron shakeup spectra of surface adsorbates: CO/Cu(100)

An nb initio static exchange approach is devised for calculations of the core-electron shake phenomenon of large species. The approach employs appropriately spin-coupled two-hole potentials for the various shakeup/ shakeoff channels. It is far extendable in the number of atoms treated, in the one-particle basis set, and in the spectral range, while restricted in correlation to full intrachannel correlation. Using cluster modeling it is implemented for shake spectra of molecules adsorbed on surfaces. A demonstration is given for the oxygen and carbon shake spectra of COCuN