GAS-PHASE ELECTRON-DIFFRACTION STUDY OF THE MOLECULAR-STRUCTURE OF CYCLOPENTADIENYL COBALT DICARBONYL, C5H5CO(CO)2

The molecular structure of C5H5Co(CO)2 has been determined by gas-phase electron diffraction. The final geometrical parameters obtained are (on the ra basis and with e.s.d.) CoC(ring) = 2.129 ± 0.006 Å, CoCO = 1.679 ± 0.004 Å, CC = 1.450 ± 0.003 Å, CO = 1.191 ± 0.004 Å, ∠ OCCoCO = 98.4 ± 0.8°; the CH bonds are bent 16 ± 4° out of the ring plane away from Co. Careful treatment of the amplitudes was required to reveal the value of the strongly correlated ∠OCCoCO angle. The data suggest that the extended Co(CO)2 plane passes through a ring carbon atom. © 1979.