Multiple-scattering approaches to near-edge x-ray absorption fine structure of N2O/Cu(100)

The nitrogen Is near-edge x-ray absorption line structure (NEXAFS) spectra of the N2O adsorbed on the Cu(100) surface have been studied by multiple-scattering cluster (MSC) and self-consistent field DV-Xalpha methods. It is shown that the N2O molecule is adsorbed on the hollow site with the adsorption height h = 3.0 +/- 0.1 Angstrom. The MSC calculation confirmed by a DV-Xalpha analysis has revealed the physical cause of the weak feature in the NEXAFS spectra mentioned above, which originates from the Is core electrons of the centre and terminal nitrogen atoms transiting into the unoccupied sigma* orbital of the N2O molecule.