Interaction of Co with an Fe(111) surface

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

“…33 It predicts that two, three, and four-fold coordinated CO species form the most stable binding geometry in Fe 3,4 , Fe 5 , and Fe 6 , respectively. The reported CO stretching frequencies for these species are significantly below our experimental values for CO atop bound to Fe [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] , as would be expected. Unfortunately, we were unable to measure clusters this small to confirm the transition from high coordination binding in small clusters to atop binding in large clusters, that has some parallels in rhodium cluster CO complexes.…”

“…For instance, for CO on Fe(111) three vibrational bands at 2000, 1805, and 1530 cm -1 were assigned to C-O stretching frequencies for carbon monoxide bound to atop, shallow hollow, and deep hollow sites on the surface, respectively. 23 CO on Fe(100) has been suggested to be tilted or side-on bound yielding a very low ν(CO) frequency around 1200 cm -1 at low coverage, whereas binding to 2-fold hollow sites (2020 cm -1 ) or on atop sites (2070 cm -1 ) was concluded to occur at higher coverage. 18,[24][25][26] These frequencies appear very high compared to the 1865 cm -1 we assign to atop bound CO adsorbed to iron clusters.…”

Structure and Surface Chemistry of Industrial Ammonia Synthesis Catalysts

“…The sticking coefficient is close to unity and remains constant up to 60% of a monolayer on Fe(l 00) [383] and up to 40% of a monolayer on Fe(111) [437] indicating the existence of a mobile precursor for the adsorption. The sticking coefficient decreases with temperature.…”

“…On Fe(111) 3 different coordinations have been observed [437]. High-resolution electron-energy-Ioss spectroscopy spectra of C + 0/Fe(111) show the Fe-C stretch at 420 cm -1 and the Fe-O stretch at 540 cm -1 [437].…”

“…For single crystal surfaces the initial enthalpy of chemisorption for CO is -105 kJ/mole on Fe(100) by temperature programmed desorption [383], -96 kJ/mole on Fe(ll 0) by temperature programmed desorption [245,436], -91 kJ/mole by temperature programmed desorption on Fe(lll) [437], and -155 kJ/mole by calorimetry on Fe(pc) [438].…”