A Density-Functional Study on the Adsorption of C2H Radical onto Small Silver Clusters

A calculation on the adsorption of C2H radical onto small silver clusters has been performed by using density functional theory. The calculated results show that Agn0/− (n = 1–6) clusters and C2H radical prefer to remain as units in the most stable structures of (C2H)2Agn0/− (n = 1–6) and C2HAgn0/− (n = 5, 6) clusters. The adsorption energies, vertical electron affinities, and the chemical hardness of the stable clusters show an obvious odd–even oscillation. Detailed natural resonance theory and natural bond order analyses show that the interaction between the C2H radical and the Agn0/− (n = 1–6) clusters in the most stable structures are mainly ionic. The stretching vibration frequency of C≡C and C–H in the ground states of clusters occurs red shifts compared with that of the C2H radical.