Mechanism of carbon-carbon bond formation by transition-metals

Both CO dissociation and dissociative methane adsorption on transition-metal catalysts can result in different carbonaceous intermediates. A very reactive carbidic intermediate produces C2+ hydrocarbons upon hydrogenation. The selectivity for chain growth versus hydrogenation depends on the metal-carbon bond strength and is optimum for ruthenium and cobalt. The recombining CH(x) fragments have an average of one hydrogen atom per surface carbon (x = 1