Calculated structures of [Au=C=Au]2+ and related systems

Calculated structures are reported for the mass-spectroscopically observed CAu22+ and CAu3+. Linear D∞h and D3h geometries are obtained, respectively. The calculated properties of other multiply-bonded species, notably PtCPt, PtCCCPt and AuCCAu are reported. The Au+ and Pt function in these systems as chemical analogues to O. Further ligands are not needed for such ‘autogenic isolobality’.