Direct observation of molecule-substrate antibonding states near the fermi level in Pd(110)- c(4 × 2)-Benzene

Abstract

Evidence for a molecule-substrate hybridized state near the Fermi level EF is presented for Pd(110)-c(4 × 2)-benzene. Observed images of adsorbed benzene near EF by scanning tunneling microscopy consist of two elongated protrusions separated by a single nodal depression with C2 symmetry. The existence of a benzene derived state near EF is also observed by metastable atom electron spectroscopy, and it is assigned to the antibonding states between the 1e1g molecular orbital of benzene and the Pd 4d orbitals by ab initio molecular orbital calculations. © 1997 American Physical Society.