Chemisorption of CO on Co(0001). Structure and electronic properties

Influence of Multielectron Excitations on the Band Structure of Adsorbate Overlayers

“…They found that the bandwidth is exponentially related to the CO-CO spacing, as expected from tight-binding calculations. 5 The system of CO adsorbed on Cu is distinctly different from all of the systems examined by Greuter et al 5 in that the valence-band spectra for Cu display an intense satellite line. This line has been identified experimentally 6 and theoretically 7 as a shake-up associated with the ionization from the 4a level.…”

“…For example the measured dispersion from the 4a energy level of ordered overlayers of CO on various substrates agrees remarkably well with theoreti-cal calculations containing only CO-CO interactions. Greuter et al 5 have correlated the measured 4a bandwidths and the CO-CO spacing for all previously studied systems. They found that the bandwidth is exponentially related to the CO-CO spacing, as expected from tight-binding calculations.…”

High coverage CO adsorption and dissociation on the Co(0001) and Co(100) surfaces from DFT and thermodynamics

“…On the other hand, the theoretical studies have also been employed to investigate CO adsorption and activation over Co surface. Ge and Neurock [19] have investigated CO adsorption and activation over the flat Co(0001), as well as the stepped Co (10)(11)(12) and Co (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24) surfaces, suggesting that CO strongly chemisorbs on these surfaces but does not show a strong dependence on the surface structure among the hexagonal closepacked (HCP) Co; the adsorption energy of CO tends to decrease as the increasing of CO coverage, in which only the coverage of 1/3, 1/4 and 1/9 ML have been considered. The studies by Cheng et al [20] on the flat and stepped Co(0001) surfaces have suggested that both the dissociative and molecular CO adsorption are needed in FTS reaction.…”

“…CO adsorption on Co surface have been experimentally characterized by the thermal desorption (TPD) [13,14], work function measurements [14,15], low-energy electron diffraction (LEED) [13][14][15][16][17] photoelectron spectroscopy [17,18]. It is found that CO adsorb molecularly on Co(0001) surface for temperatures up to 450 K [13,15].…”

Density-functional study of the CO adsorption on ferromagnetic Co(0001) and Co(111) surfaces

“…It is interesting that coadsorbed K moves CO molecules to three-fold fcc and hcp sites [20]. For higher CO coverage, new adsorption sites become occupied and complicated overlayer phases are formed [17,18,21], geometry of which is not completely clarified. In the realm of thin-film magnetism, the CO adsorption on Co (especially in Co (1 1 1)) is of special interest because of its ability to switch the magnetization orientation [22][23][24].…”