Synthesis of a Trigold Monocation: An Isolobal Analogue of [H sub(3)] super(+)

Isolobal and isolatable: A triangular [L sub(3)Au sub(3)] super(+ ) ion, bearing N-heterocyclic carbene ligands (L), is crystallographically characterized (see structure; Auyellow, Cgray, Nblue). Density functional theory suggests full valence delocalization among the gold atoms, with the HOMO composed largely of gold 6s orbitals and the LUMO comprising a degenerate pair. This orbital picture is analogous to that of [H sub(3)] super(+).