The phosphino-stibine ligands (o-PPh2C6H4)(2)SbR [R =o-PPh2C6H4(L1), Ph (L2), Cl (L3)] were incorporated into tungsten and molybdenum carbonyl complexes leading to the formation ofcis-[W(CO)(4){(o-PPh2C6H4)(2)SbR}] [R =o-PPh2C6H4(1), Ph (2), Cl (3)],fac-[W(CO)(3){(o-PPh2C6H4)(3)Sb}] (4),fac-[W(CO)(3){(o-PPh2C6H4)(2)SbCl}] (5),fac-[(W(CO)(3){(o-PPh2C6H4)(2)Sb})(2)] (6),fac-[Mo(CO)(3){(o-PPh2C6H4)(2)SbR}] [R =o-PPh2C6H4(7), Ph (8), Cl (9)]. Compounds1and4were allowed to react with MX salts with M = Cu, Ag, Au and X = Cl-, [PF6](-), respectively. These reactions yieldedcis-[W(CO)(4){(o-PPh2C6H4)(3)Sb}{MCl}] [M = Cu (10), Ag (11)],cis-[W(CO)(4){(o-PPh2C6H4)(2)Sb}{AuCl(o-PPh2C6H4)}{AuCl}] (12)cis-[(W(CO)(4){(o-PPh2C6H4)(2)Sb})(2)AuCl] (13),cis-[W(CO)(3)(mu-CO){(o-PPh2C6H4)(3)Sb}{Cu}][PF6] (14),cis-[W(CO)(4){(o-PPh2C6H4)(3)Sb}{AgMeCN}][PF6] (15),cis-[W(CO)(4){(o-PPh2C6H4)(3)Sb}{Au}][PF6] (16)cis-[W(CO)(2)(mu-CO){(o-PPh2C6H4)(3)Sb}{Cu-2(mu-Cl)(2)}] (17),fac-[W(CO)(3){(o-PPh2C6H4)(3)Sb}{AuCl}] (18), andfac-[W(CO)(2)(mu-CO){(o-PPh2C6H4)(3)Sb}{ML}][PF6] [M = Cu, L = MeCN (19), M = Ag, L = MeCN (20), M = Au (21)]. Complexes10-21all show metal-metal distances below the sum of the corresponding van der Waals radii. The proximity of the two metal centers is especially significant in19-21, indicating the presence of metal-metal bonding.