STABLE RECONSTRUCTION OF THE POLAR (111) SURFACE OF NIO ON AU(111)

Several theoretical studies of the stability of (111)-terminated ionic crystals with the NaCl structure have predicted that the crystal Madelung energy can be stabilized by a simple surface reconstruction. However, previous attempts to grow (111)-terminated crystals have resulted in either unreconstructed or faceted surfaces. We demonstrate that deposition of Ni in an oxygen atmosphere onto a Au(111) substrate held at T approximately 300-degrees-C results in the growth of a stable p(2 X 2) reconstructed NiO(111) and resolve the atomic details of this surface with our scanning tunneling microscope.