Electron-impact study of some binary metal carbonyls

The mass spectra and appearance potentials for the major ions from Ni(CO) 4 , Fe(CO) 5 , Cr(CO) 6 , Mo(CO) 6 , W(CO) 6 , and V(CO) 6 have been measured. Heats of formation have been calculated for 39 ions of the type M(CO) n + , where M = Ni, Fe, Cr, Mo, W, and V. The mean metal–carbon bond dissociation energies have been calculated for both the neutral molecules and the parent ions. From a comparison with the available thermochemical data for the neutral molecules it is concluded that the mean vanadium–carbon bond dissociation energy is 28 kcal/mole and the heat of formation of V(CO) 6 vapor is − 204 kcal/mole.