In recent years, density functional theory (DFT) calculations have played a crucial role in the expansion of f-element chemistry through contributing to the discovery of newly accessible metal oxidation states and novel electronic structures for lanthanide (Ln) and actinide (An)-containing species. With the purpose of maintaining and extending the utility of such computational approaches, this thesis discusses a few recent applications of DFT towards the characterization and theoretical prediction of new Ln and An-based species.