Generalization of Natural Bond Orbital Analysis to Periodic Systems: Applications to Solids and Surfaces via Plane-Wave Density Functional Theory

Natural bond orbital (NBO) analysis is a powerful analysis technique capable of generating intuitive chemical representations of otherwise complex quantum mechanical electronic structure results, yielding a localized Lewis-like description of bonding and reactivity. We generalize this algorithm to periodic systems, thus expanding the scope of NBO analysis to bulk materials and/or periodic surface models. We employ a projection scheme to further expand the algorithm's applicability to ubiquitous plane-wave density functional theory (PW DFT) calculations. We also present a variety of example applications: examining bulk bonding and surface reconstruction and elucidating fundamental aspects of heterogeneous catalysis all derived from rigorous underlying PW DFT calculations.