An experimental and theoretical investigation into the binding interactions of silver cluster cations with ethene and propene

Sequential bond dissociation energies (BDEs) and association entropies for the attachment of C2H4 ligands to ground-state Agm+ (m = 3–13) clusters and for the attachment of C3H6 ligands to ground-state Agm+ (m = 3–9) clusters have been measured using temperature-dependent equilibrium methods. Variations in metal–ligand BDEs are examined in detail both as a function of sequential ligand addition to a given Agm+ cluster and as a function Agm+ cluster size for the first ligand additions. With the exception of the Ag6+ and Ag7+ clusters, BDEs for the loss of a ligand from the Agm+(L) (m = 3–13, L = C2H4; m = 3–9, L = C3H6) clusters decrease as the size of the silver clusters increase. Electronic structure calculations at the DFT-B3LYP level were performed in order to determine the vibrational frequencies, rotational constants and geometries of the silver–alkene clusters of interest as well as the nature of the bonding of these clusters and its variation with core ion coordination.