The reaction of FeCo2 （CO）9(μ3-S ) with O [P（SCH2）2]2 ligand in mixed solvents of hexane and dichloromethane at 50℃ leads to the compound FeCo2 （CO）7 （μ3）-S) （O [P（SCH2）2]2）. The compound has been characterized by element analysis, IR, 1H NMR, MS spectfa and a single crystal X-ray structure determination.Its structure consists, of a distorted tetrthedral core FeCo2S in which the Co（1）, Co（2）, Fe, and S atoms occupy a vertex of the tetrahedron respectively, and the P atoms of O [P（SCH2）2]2 bonded to two Co atoms in their axial positions.
