How carbon monoxide bonds to metal surfaces

Abstract

An analysis is presented of the similarities and differences in the bonding of CO to Ni(100), Ni(l 11), Co(0001), Fe(110), Cr(110), and Ti(0001). The primary interactions in every case are the expected forward and back donation, the mixing of CO 5 with surface dz2 and s states, and the mixing of CO 2:r with metal dXZi>.z. The latter interaction is dominant. Projections of the density of states and crystal orbital overlap population curves show these interactions clearly. As the metal changes from Ni to Ti, the effects of the rise of the Fermi level and the diffuseness of the d orbitals combine to put more and more electron density into 2 of CO. This is why CO dissociates on the earlier transition-metal surfaces. Our studies of surface coverage show little effect on the diatomic dissociation. There is some indication in the calculations that higher index surfaces should dissociate CO more readily than the lower index ones, but the effect is smaller than that of changing the metal.

Probing C–O bond activation on gas-phase transition metal clusters: Infrared multiple photon dissociation spectroscopy of Fe, Ru, Re, and W cluster CO complexes

“…This results in more π back-bonding to the CO antibonding 2π orbital, and the weakening of the C-O bond, until CO binds dissociatively. 53 Consequently, the C-O stretching frequency for CO adsorbed on clusters of early transition metals are at lower frequencies than those of the later transition metal clusters. Similarly, the Fermi energy level becomes increasingly lower moving down a family, and the C-O stretching frequency increases successively when going from the 3d metal to the heavier homologues.…”

The DFT+U: Approaches, Accuracy, and Applications

“…In catalysis, for example, understanding the adsorption mechanism of species on catalytic surfaces-mainly electrodes-is essential in order to formulate a design principle for the prefect catalyst that can reach the optimum efficiency for a desired electrochemical process [81][82][83]. Typically, the adsorption of CO on metal surface is widely acknowledged as the prototypical system for studying molecular chemisorption [84][85][86][87].…”

The Interfacial Reaction of CO with Liquid Iron by 13C18O-12C16O Isotope Exchange Reaction

“…The reaction of CO 2 or CO with liquid iron is one of the most important reactions in iron and steelmaking process. In the field of inorganic or catalysis chemistry, it is well known that CO dissociation reaction (1) CO(g) AE C (ad)ϩO(ad) ...................... (1) occurs quite easily on Fe surface, surprisingly even at 195 K. 1) Its fundamental reaction mechanism was extensively studied and well established.…”

“…In the field of inorganic or catalysis chemistry, it is well known that CO dissociation reaction (1) CO(g) AE C (ad)ϩO(ad) ...................... (1) occurs quite easily on Fe surface, surprisingly even at 195 K. 1) Its fundamental reaction mechanism was extensively studied and well established. 2,3) However, the rate constant of the reaction (1) on liquid iron surface was not established. In the previous studies [4][5][6][7] of CO reaction on liquid iron the rate was all found to be controlled by liquid phase mass transfer.…”