Ab initio calculation of graphite surface-bulk core-level splitting -: art. no. 073403

The origin of two carbon 1s components observed recently in photoelectron energy spectra of graphite have been analyzed quantitatively by means of electronic structure and total-energy calculations for supercell structures. The all-electron pseudopotential technique within the local-density approximation was applied. Two different contributions to the core-level shift were studied: the initial-state shift and the final-state shift from a core-hole relaxation. The results of calculations show that final-state relaxations plays a crucial role and that the doublet cannot be understood within an initial-state picture.