A novel high nuclearity bimetallic cluster: The crystal structure of [N(PPh 3) 2][Ag 6Cu 7(C 2Ph) 14

Abstract

An X-ray diffraction study of the high nuclearity complex [N(PPh 3) 2][Ag 6Cu 7(C 2Ph) 14] has shown it to be a novel 13-atom bimetallic anionic cluster [Ag 6Cu 7(C 2Ph) 14] − with two types of copper atoms, one inside the body of the cluster and six on its surface. The surface atoms have a distorted trigonal bipyramidal geometry whereas the internal copper atom is linearly coordinated by two C 2Ph groups in addition to displaying six CuAg bonding interactions with three tetranuclear [Ag 2Cu 2(C 2Ph) 4] subclusters. Thus the internal copper atom essentially exhibits eight-coordination. All the silver atoms have a bent two-coordinate geometry as far as CuAgCu metal bonding is concerned. These atoms are also asymmetrically π bonded to alkyne groups on the phenyl moieties attached to the adjacent copper atoms. This complex represents a new class of Group 1B metal clusters with a bonding pattern not observed previously.