The reaction of mono-Cr(CO)(3) complexes of a number of aromatic compounds containing two arene groups with the Mn(CO)(3)(+) transfer agent [(naphthaleneMn(CO)(3)](+) gave new Cr/Mn diarene heterobimetallic compounds, e.g., (OC)(3)Cr(eta(6)-C6H5CH=CHC6H5-eta(6))Mn(CO)(3)(+). This and two others of these compounds were characterized by X-ray diffraction. The two metal carbonyl groups were found to be on the same face of the aromatic hydrocarbon molecules in a syn arrangement.