L. Thompson - Single reference wavefunctions as first-order approximations for efficient variational and orthogonal description of multistate reaction pathways

Speaker: L. Thompson, University of Louisville, Department of Chemistry

Abstract: Computational simulation is vital to understand and corroborate mechanistic and spectroscopic experiments of excited states processes. However, methodologies for simulating excited states are limited, either due to inability to describe important effects away from the vertical excitation region (e.g. response based approaches), or due to poor computational scaling (e.g. configuration-interation based approaches). In this talk, I will discuss our developments towards a hierarchy of efficient computational approaches that can simulate excited state reaction paths without limitation as to the nature of electronic states involved. I will show our first steps in constructing models that behave variationally with regard to any electronic state and yield orthogonal solutions consisting of nonlinearly optimized basis solutions which form the set of first-order approximations to different electronic states. In addition, I discuss our approaches for rapidly obtaining sets of nonlinearly optimized solutions that approximate different electronic states for use as initial basis states in the models. Applications that demonstrate the utility of the method to the study of photocatalysis will be discussed.