We report the synthesis, structural characterisation and solution-phase dynamics of a series of polyaromatic hydrocarbon complexes of the 12-electron {Rh(PiBu 3 ) 2 } + fragment. Crystal structures of this fragment with benzene, naphthalene, anthracene, pyrene, triphenylene and coronene are described, alongside their solution NMR spectroscopic data.

Density functional theory has been used to probe the structures and solution dynamics of a series of polyaromatic hydrocarbon complexes of the 12-electron fragment {Rh(PiBu 3 ) 2 } + . These studies suggest that the strength of the binding of the metal to the hydrocarbon surface is controlled by the electronic demands of both the metal (16-electron configuration) and ligand (maximum retention of aromaticity). In