Formation of new organometallic W/Cu/S clusters from reactions of [{(η5-C5Me5)WS3}3Cu7(MeCN)9](PF6)4 with donor ligands. Crystal structures and optical limiting properties of [(η5-C5Me5)WS3Cu3(Py)6](PF6)2, [(η5-C5Me5)WS3Cu3Br(PPh3)3](PF6), and [(η5-C5

Three new W/Cu/S clusters [(η5-C5Me5)WS3Cu3(Py)6](PF6)2, [(η5-C5Me5)WS3Cu3Br(PPh3)3](PF6), and [(η5-C5Me5)WS3Cu4(Py)Cl(dppm)2](PF6)2 were prepared from reactions of [{(η5-C5Me5)WS3}3Cu7(MeCN)9](PF6)4 with pyridine, PPh3 and dppm. The structures of the three compounds were characterized by X-ray crystallography and their optical limiting properties in solution were studied.