Collect. Czech. Chem. Commun. 1992, 57, 2481-2493

FEM Study of Oxidized Tungsten Surfaces

Jan Šotolaa, Vladimir Savkinb and Zlatko Knora

a J. Heyrovský Institute of Physical Chemistry and Electrochemistry, Czechoslovak Academy of Sciences, 182 23 Prague 8, Czechoslovakia
b Institute of Chemical Physics, Russian Academy of Sciences, Moscow, Russia


Surface reconstruction of tungsten induced by oxygen chemisorption in the temperature range 300 K ≤ T ≤ 2200 K, has been investigated by means of FEM. Two types of surfaces have been used in this study: (i) hemispherical tungsten tips exposing small low index planes and stepped regions to the gas phase; (ii) polyhedral tungsten tips exposing large densely populated planes. A model for the reconstruction of a (100) plane is presented, explaining all the phenomena observed by FEM, TDS, LEED and MBS.