INFRA-RED SPECTRA OF CARBON MONOXIDE ON EVAPORATED NICKEL FILMS

Thin nickel films deposited at low temperatures under ultrahigh vacuum conditions give spectra with CO which are similar to those previously reported with supported nickel and with films deposited under poor vacuum conditions. It is believed that a major part of the strongly adsorbed CO is inactive in the spectra. Particle size effects are important. Small particles give enhanced absorption at both high and low frequencies. Anomalous transmission peaks are attributed to the effect of a species on the smaller particles with a particularly high extinction coefficient. Such effects are expected to occur only with thin films. © 1969.