Peraurated nickel carbide carbonyl clusters: the cationic [Ni6(C)(CO)8(AuPPh3)8]2+ monocarbide and the [Ni12(C)(C2)(CO)17(AuPPh3)3]- anion containing one carbide and one acetylide unit.

Two new peraurated Ni-carbide carbonyl clusters have been prepared and structurally characterized, i.e. [Ni6(C)(CO)8(AuPPh3)8](2+) and [Ni12(C)(C2)(CO)17(AuPPh3)3](-). The latter is the first molecular cluster containing one carbide atom and one tightly bonded C2-unit. These display sub-van der Waals contacts suggesting the incipient formation of more extended C-C bonding.