V - MSpace at the University of Manitoba

providing improved electronic energies. Among the popular techniques, which use the
HF wave function as a starting point, are many-body perturbation theory, coupled-cluster
theory, and configuration interaction (CI). Each of these methods yields more accurate
results than the HF model alone, but they are computationally much more demanding,
and as a result make obtaining accurate predictions for moderately large molecules of
chemical interest difficult [27, 28].
2.1 Density Functional Theory
The 1998 Nobel Prize in Chemistry recipients John Pople and Walter Kohn were
recognized for their respective participation to the convergence of the traditional quantum
chemical techniques (Pople) with that of the relatively new density functional
methodology (Kohn).
Advances in accurate and expedient quantum chemical calculations on inorganic
and organometallic actinide molecules of reasonable size, has only recently become
possible. Actinide chemistry in particular with its relatively unexplored f-element
chemistry and inherent experimental challenges merits further computational
investigation that often results in time savings for experimentalists [18, 21-24].
One of our aims is to test the abilities of DFT, and the many methods used in
combination with it, at providing chemically accurate results. Only recently with
advances in computing power and the growing acceptance of DFT methods, which
incorporate electron correlation and relativistic effects, have computational chemical
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