The first experimental evidence for the presence of a cyclic form of ozone was reported for 3 air-stable reconstructions of (111) surfaces when annealed above 1450C. The (111)-(v3 x v3)R30º surface consisted of equilateral O trimers, while the (111)-(2 x 2) and (111)-(2v3 x 2v3)R30º surfaces involved periodic arrangements of trimers and single O atoms. The O trimers appeared to be centered over underlying Mg atoms. These structures better fitted transmission electron diffraction data than did the neutral-plane faceting-based models which had been proposed for the polar (111) surface.

Cyclic Ozone Identified in Magnesium Oxide (111) Surface Reconstructions. R.Plass, K.Egan, C.Collazo-Davila, D.Grozea, E.Landree, L.D.Marks, M.Gajdardziska-Josifovska: Physical Review Letters, 1998, 81[22], 4891-4