Angle-resolved synchrotron-radiation photoemission results are presented that examine the evolution of the Au(100)-(1×1) surface state at the epitaxial Cr/Au(100) interface as a function of Cr thickness. At submonolayer coverages, two-dimensional Cr islands form and stabilize the (1×1) termination of the substrate, as judged by the simultaneous detection of both the Au-(1×1) and -(5×20) surface states. The Au(100)-(1×1) surface state persists in the outer Au layer for 1 monolayer (ML) of Cr or Au(100). As the Cr overlayer thickness is increased from 1 to 2 ML, the interface state is modified and its binding energy changes from 1.9 to 2.6 eV. For Cr coverages in excess of 3 ML, the Au state couples with bulk states and vanishes. The Au surface-interface state is reestablished by the growth of an ultrathin Au layer over the 2–3-ML-thick epitaxial Cr layers, and its binding energy shifts back toward $E_F$. The results are discussed in terms of changes in the surface-interface potentials during the evolution of the overlayer.

• Received 24 November 1986

DOI:https://doi.org/10.1103/PhysRevB.35.5892