Density functional calculations on CO attached to PtnRu(10-n) (n=6-10) clusters

B3LYP and SCF-X alpha calculations have been performed on PtnRu(10-n)CO (n = 6-10) clusters. The work aims to simulate the adsorption of CO on the (11 1) surface of platinum metal and to examine the electronic effects that ari se when some Pt atoms are replaced with Ru. Adsorption energies and Pt-C an d C-O stretching frequencies have been calculated for each cluster. Ru does affect the electronic structure of the clusters, the calculated adsorption energies, and frequencies, the Pt-C frequency more than the C-O. The donat ion-backbonding mechanism that accompanies the shift in CO stretching frequ ency that occurs when CO adsorbs on platinum does not explain the differenc es in frequency shift observed in CO on various Pt/Ru surfaces. (C) 2000 Jo hn Wiley & Sons, Inc.