In order to gain some insight into the stability of configuration and the bonding in the novel disulfide-containing complex [(η-C 5H 5) 2Fe 2S 2(SC 2H 5) 2], electrochemical properties of this compound and its SCH 3 and SCH 2C 6H 5 analogues were studied in various solvents and the magnetic properties of a subsequently isolated paramagnetic monocation were investigated. The cyclic voltammogram of [(η-C 5H 5) 2Fe 2S 2(SC 2H 5) 2] shows a reversible one-electron oxidation at E 1 2 = +0.21 V and a quasi-reversible one-electron oxidation at E 1 2 = +0.90 V (vs.saturated calomel electrode). The stable monocation has been electrochemically synthesized and the magnetic suceptibility shows a simple paramagnetic behavior with one unpaired electron per dimeric unit. Frozen solutions of this species at 103K yielded anisotropic ESR spectra with g 1 = 2.135, g 2 = 1.976, and g 3 = 1.934. Labeling the complex with 33S in the disulfide bridge resulted in no observable hyperfine splitting or line broadening in the ESR. The dicationic species is unstable with respect to loss of the S 2 bridge and formation of a solvent-ligated dication, [(η-C 5H 5)Fe(NCCH 3)(SC 2H 5)] 2 2+, isolated by electrolysis of the monocation at +1.2 V in CH 3CN.