Three polynuclear complexes, [Pt-2(II)(dppm)(2)(mu-eta(1):eta(1)-HC=CFc)Cl-2] (1), [Ag-3(I)(dppm)(3)(mu(3)-eta(1)-CdropCFc)].2CF(3)SO(3) (2.2CF(3)SO(3)) and [Cu-3(I)(dppm)(3)(mu(3)-eta(1)-CdropCFc)(2)].PF6 (3.PF6), were synthesized and characterized using single-crystal X-ray diffraction, UV-vis spectroscopy, and voltammetry (dppm = bis(diphenylphosphino)methane; Fc = ferrocenyl). Compound I is an A-frame complex in which two POT ions are bridged by two dppm and one ethynylferrocene. Both 2.2CF(3)SO(3) and 3.PF6 are composed of trimetallic Ag-3(I) and Cu-3(I) cores bridged by three dppm and capped with one and two ferrocenylacetylides, respectively. All complexes exhibit reversible Fc oxidation in their cyclic voltammograms (CV), ranging from -48 +/- 10 to 235 +/- 10 mV vs Ag/AgNO3 (0.1 M). The reduction potential difference between silver and copper complexes is mostly due to intramoleuclar electrostatic interactions. A weak intervalence charge-transfer transition at 1250 nm arising from the mixed-valence 3(2+) is observed in the solution near-infrared absorption spectrum of a mixture of 3.PF6 and ferrocenium hexafluorophosphate (Cp2FePF6). Cyclic and differential pulse volatmmograms of 3.PF6 show two reversible Fc oxidations separated by 110 +/- 14 mV, giving a comproportionation constant K-c of 77 +/- 30. The stability of the mixed-valence complex 3(2+) arises mainly from the reduction of electrostatic repulsion and statistical distribution.