The Ag/MgO(100) interface has been studied by EXAFS. At room temperature, in agreement with previous investigations, silver at low coverage is shown to form a two-dimensional layer at the MgO(100) surface. EXAFS data demonstrate that the lattice parameter of the silver overlayer is expanded so as to fit the MgO parameter to give rise to an interface having ${\mathrm{}\left(100\right)\mathrm{}}_{\mathrm{AG}}$∥${\mathrm{}\left(100\right)\mathrm{}}_{\mathrm{MGO}}$ and ${\mathrm{}\left[100\right]\mathrm{}}_{\mathrm{AG}}$∥${\mathrm{}\left[100\right]\mathrm{}}_{\mathrm{MGO}}$ orientation. Interface Ag atoms are atop the oxygen atoms of the MgO(100) surface at a distance of 2.53±0.05 Å.

• Received 5 July 1995

DOI:https://doi.org/10.1103/PhysRevB.53.R1737