WHAT DETERMINES THE STRUCTURES FORMED BY OXYGEN AT LOW-INDEX SURFACESOF COPPER

This article reviews structural details from tensor LEED analyses for three oxygen on copper surfaces, specifically those designated Cu(11O) -(2x1)-O, Cu(110)-c(6x2)-O and Cu(100)-(2 root 2x root 2)R45 degrees-O . Certain common features are identified and discussed. It appears tha t these particular structures receive some stability from being able t o fit O-Cu-O building blocks, of the sort needed to construct bulk Cu2 O, on to the Cu substrates. Each O atom maintains a four-coordinate st atus, while simultaneously allowing reasonable O-Cu bond lengths. Comp arisons are made with other related systems, namely O at Ni and N at C u surfaces.