Surface electronic structure of CeN

The first detailed all-electron local-density study of the surface electronic structure of an f-electron compound, CeN(001), is presented using the full-potential linearized-augmented-plane-wave method. Small but significant differences between the surface and bulk predictions are analyzed using recent photoemission data. In particular, attention is addressed to a surface chemical shift of 1 eV for the 4f states in CeN that has been deduced from photoemission experiments. The results of the present study of the CeN(001) surface do not support this picture. Rather, it is suggested that the 4f photoemission peak at 1.2 eV below the Fermi level might be caused by (surface) vacancies in CeN, or by more complicated final-state effects.