Structural investigation of the Rh(110)-c(2x2)-CN phase - art. no. 085422

The Rh(110)-c(2x2)-CN phase has been examined by means of scanning tunnelin g microscopy (STM) and full dynamical low-energy electron diffraction (LEED ). From STM large c(2 x 2) domains are observed. The detailed LEED-IV struc tural analysis indicates that CN is located in the grooves of the (110) sur face, approximately atop second layer rhodium atoms. The CN molecules lie a lmost flat with their bond axes oriented perpendicular to the rhodium troug hs. An outward relaxation of the first substrate interlayer distance and a strong buckling of the second Rh layer are induced by CN adsorption. Calcul ated and experimental intensity curves are in good agreement. An exhaustive set of other possible adsorption sites and configurations was tested and e xcluded on the basis of reliability-factor analysis.