Density functional study of acetylene and ethylene adsorption on Ni(111)
نویسندگان
چکیده
Optimized geometries and adsorption energies obtained from non-local density functional calculations are presented for the adsorption of acetylene and ethylene on Ni(lll). Two cluster models, Ni4 and Nil4, are used. The best adsorption modes are #bridging and di-cr for acetylene and ethylene, respectively. In these orientations the overlap between the adsorbate frontier orbitals and the metal cluster orbitals is important, and the donation and back-donation of electrons are large. The calculations support the picture of strongly distorted adsorbates on the surface.
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