Twenty new Fe-S cluster complexes having a general formula (μ-RS) (μ-R’S)-Fe_2(CO)_6 were synthe-sized through reduction of -S_2Fe_2(CO)_6 with RMgC1, followed by in situ nucleophilic substitution of RXwith the intermediates (μ-RS)(μ-C1MgS)Fe_2(CO)_6. Besides the data of m.p., C/H, IR and ~1H NMRdetermined, the conformers of these complexes and the ratios of the conformers have been discussed ac-cording to the chemical shifts and integrated values of methyl, methylene and methyne groups attachedto the sulfur atoms in the complexes. Twenty new Fe-S cluster complexes having a general formula (μ-RS) (μ-R’S) -Fe_2 (CO) _6 were synthe-sized through reduction of -S_2Fe_2 (CO) _6 with RMgC1, followed by in situ nucleophilic substitution of In addition to the data of mp, C / H, IR and ~ 1H NMRdetermined, the conformers of these complexes and the ratios of the conformers have been discussed ac (RX-the intermediates) (μ-C1MgS) Fe_2 -cording to the chemical shifts and integrated values ​​of methyl, methylene and methyne groups attachedto the sulfur atoms in the complexes.