MOLECULAR-STATES OF CO INTERACTION WITH 3D-METAL SURFACES

Ab initio molecular-orbital calculations of the carbonyls of 3d transi tion metals are used to indicate the tilted metal-CO complex as the mo lecular state precursor of CO dissociation on 3d surfaces. The present resonating-valence-bond mechanism for CO dissociation suggests that t he tilted state may be observed in all dissociative 3d surfaces, that is, from Sc to Fe. Calculations of scandium monocarbonyl are used to u nderstand the effects of inclination on electronic configuration and c alculations of Cr2CO cluster are used to study CO dissociation on the Cr(110) surface and to explain the substantial reduction of CO binding modes found for the tilted state.