Dean M. Philipp, Richard P. Muller, and William A. Goddard, III.
for the slides from the full talk.
Abstract: Quantum chemical calculations using the B3LYP density
functional method as implemented by the Jaguar program were used to look
at chain propagation for polyethylene and polypropylene polymerization
by late metal homogeneous catalysts. Model catalysts were used to determine
the effects of varying the metal, coordinating ligands, and monomer units
(propylene versus ethylene). General trends of the ethylene complexation
energy and the insertion energy barrier increasing as the metal was changed
to one further down or further to the left in the periodic table were found
(though the reverse was actually the case for the insertion barrier for
the first transition series). The weaker the trans influence of the coordinating
ligand, the larger the observed ethylene complexation energies and insertion
energy barriers. Finally, it was found that using propylene instead of
ethylene yielded slightly larger monomer complexation energies and insertion
barriers, while two possible propagation pathways for polypropylene were
This research was supported The Dow Chemical Company.