Pa. Hintz et Km. Ervin, NICKEL GROUP CLUSTER ANION REACTIONS WITH CARBON-MONOXIDE - RATE COEFFICIENTS AND CHEMISORPTION EFFICIENCY, The Journal of chemical physics, 100(8), 1994, pp. 5715-5725
Reactions of Ni(n)-(n = 3 - 10), Pd(n)-(n = 3 - 8), and Pt(n)-(n = 3 -
7) with CO are studied in a flow tube reactor. Bimolecular rate coeff
icients are measured for the association reaction of CO adsorbing on t
he cluster surface. The rate coefficients range from about 10% of the
collision rate for the trimer anions to near the collision rate for cl
usters larger than four atoms. The maximum number of CO molecules that
bind to each cluster is determined. Whereas the saturation limits for
nickel are typical for an 18 electron transition metal, the limits fo
r platinum are lower, reflecting the electron deficient structures obs
erved in condensed phase chemistry. The CO saturated palladium cluster
s represent the first examples of saturated binary palladium carbonyl
compounds. Comparisons are made to similar studies on metal cation and
neutral clusters and also to surface scattering studies of nickel gro
up metals.