Modeling Excited States with Restricted Determinants in State Averaged Resonating Hartree-Fock

Nonadiabatic molecular dynamics (NAMD) simulations provide atomistic insights into photochemical processes, rendering them essential to the progression of the field. However, a major challenge for NAMD simulations lies in obtaining balanced representations of diverse excited states without sacrificing computational affordability. We present Resonating Hartree-Fock (ResHF) as a promising electronic structure theory candidate for NAMD simulations. We hypothesize that ResHF's nonorthogonal Slater determinant manifold will allow for balanced representation of both conical intersections and charge transfer states, all the while boasting mean field scaling. In our current work, we present state averaged (SA) ResHF excited state wavefunctions that are built out of restricted Hartree-Fock determinants. We then model aniline excited states to showcase the ability of SA-ResHF to avoid charge transfer errors common to state averaged Complete Active Space methods.