The structure of the mixed-metal cluster anion [FeOs3H(CO)13]– as its [N(PPh3)2]+ salt

The mixed-metal cluster anion [FeOs3H(CO)13]– has been prepared by the reaction of [N(PPh3)2]2[Fe3(CO)11] with [Os3(CO)12]. The compound crystallises in the triclinic space group P, with a= 9. 184(1), b= 15.223(2), c= 19.152(2)A, α= 107.75(1), β= 102.81 (1), γ= 93.67(1)°, and Z= 2. The four metal atoms define a tetrahedron with two carbonyl ligands semi-bridging between the iron atom and two of the osmium atoms, and the hydride lying along an osmium–osmium edge. The cation has the usual bent geometry with an angle P–N–P of 146.3(7)°.