Stable Cu(II) co-ordination complexes in the gas phase

New results are presented from a technique which appears capable of producing `tailor-madeʹ complexes from a variety of metals and ligands. Data are presented for [Cu.({CH3}2CO)n]2+, [Cu.(C2H4)n]2+ and [Cu.(NH3)n]2+. Two of these, [Cu.({CH3}2CO)n]2+and [Cu.(C2H4)n]2+, conform to the expected pattern in terms of the most stable co-ordination number and current views of bonding. However, the results for [Cu.(NH3)n]2+ complexes do not fit any of the existing pictures of Cu(II) solvated in concentrated ammonia. To account for this observation, it is proposed that hydrogen bonding makes an important secondary contribution to the solvation of Cu(II).