Several theoretical studies of the stability of (111)-terminated ionic crystals with the NaCl structure had predicted that the crystalline Madelung energy could be stabilized by a simple surface reconstruction. However, previous attempts to grow (111)-terminated crystals had resulted in either unreconstructed or faceted surfaces. It was demonstrated that deposition of Ni in an oxygen atmosphere onto a Au(111) substrate held at ∼300C resulted in the growth of a stable p(2 x 2) reconstructed NiO(111) and resolved the atomic details of this surface using scanning tunnelling microscopy.

Stable Reconstruction of the Polar (111) Surface of NiO on Au(111). C.A.Ventrice, T.Bertrams, H.Hannemann, A.Brodde, H.Neddermeyer: Physical Review B, 1994, 49, 5773-6