Kj. Lyons et al., ADSORPTION OF CARBON-MONOXIDE ON IR(110) INVESTIGATED BY INFRARED REFLECTION-ABSORPTION SPECTROSCOPY, Surface science, 325(1-2), 1995, pp. 85-92
The adsorption of carbon monoxide on the Ir(110) surface at 300 K has
been investigated with Fourier transform infrared reflection-absorptio
n spectroscopy. A single band was observed that shifted up from a low-
coverage value of 2001 cm(-1) to a saturation-coverage limit of 2086 c
m(-1). This band is attributed to the carbon-oxygen stretching mode of
a molecule adsorbed on top of a surface iridium atom. This frequency
shift was separated into a contribution due to dipole-dipole interacti
ons and a smaller contribution from chemical effects (d-electron compe
tition) by using isotopic substitution. Employing knowledge of the str
ucture of the reconstructed Ir(110) surface and temperature-programmed
desorption spectra measured at various coverages, an adlayer model is
proposed to reconcile a single adsorption site with the temperature-p
rogrammed desorption data.