Vc. Gibson et al., The nature of the active species in bis(imino) pyridyl cobalt ethylene polymerisation catalysts, CHEM COMMUN, (21), 2001, pp. 2252-2253
Studies on cobalt ethylene polymerisation catalysts bearing bis(imino) pyri
dine ligands strongly indicate that the activated species is not the antici
pated cobalt(II) alkyl cation.