Evaluating the Role of π-Donor Ligands in Transition Metal Chemistry. Applications of Fenske-Hall Molecular Orbital Calculations and Mulliken Population Analyses

Abstract

Fenske-Hall molecular orbital calculations are used to probe the electronic structure and bonding of amide and alkoxide ligands bound to a transition metal. A “frozen π-orbital” method is introduced and used to separate σ and π-bonding effects of these ligands to the metal. Mulliken population analyses are used as a relative measure of π-donor ability of the alkoxide ligand with varying M-O distance, M-O-C(H) angle, and dⁿ electron count. Population analyses are also used to gauge the effect of π-donor ligands on the π-acceptor role of ancillary ligands such as carbonyl and isocyanide.