Iridium carbon bond energies

M. J. Wax, J. M. Stryker, J. M. Buchanan, C. A. Kovac, and R. G. Bergman, Reversible C—H Insertion/Reductive Elimination in ( 5-Pentamethylcyclopentadienyl)(trimethyl-phosphine)iridium Complexes. Use in Determining Relative Metal-Carbon Bond Energies and Thermally Activating Methane, J. Am. Chem. Soc. 106, 1121-1122 (1984). 

These trends are consistent with observations made to characterize the chain growth of surface carbon that was deposited by methane decomposition. In a row of the periodic table, the selectivity to hydrocarbon formation was foimd to increase from right to left for example, palladium shows a lower selectivity than ruthenium 111,112). Metals such as platinum and iridium are characterized by higher selectivities for chain growth initiated from "Cl" species than other metals because of their relatively high M—C bond energies. However, platinum and iridium are unsuitable as Fischer-Tropsch catalysts because the dissociation of CO is too slow. 

---