CYCLIC OZONE IDENTIFIED IN MAGNESIUM-OXIDE (111) SURFACE RECONSTRUCTIONS

We report the first experimental evidence of the cyclic form of ozone, found in three air stable surface reconstructions of MgO (111) anneal ed above 1450 degrees C. The MgO (111)-(root 3 x root 3)R30 degrees su rface consists of equilateral oxygen trimers while the MgO (111)-(2 x 2) and MgO (111)-(2 root 3 x 2 root 3)R30 degrees surfaces are periodi c arrangements of trimers and single oxygen atoms. The oxygen trimers appear to be centered over underlying Mg atoms. The structures fit tra nsmission electron diffraction data better than neutral plane faceting based models proposed for the polar MgO (111) surface. [S0031-9007(98 )07807-7].