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Published on: October 9, 2020
Configuration interaction singles with spin-orbit coupling: Constructing spin-adiabatic states and their analytical
Nicole Bellonzi1, Gregory R Medders1, Evgeny Epifanovsky2
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Abstract:
For future use in modeling photoexcited dynamics and intersystem crossing, we calculate spin-adiabatic states and their analytical nuclear gradients within configuration interaction singles theory. These energies and forces should be immediately useful for surface hopping dynamics, which are natural within an adiabatic framework. The resulting code has been implemented within the Q-Chem software and preliminary results suggest that the additional cost of including spin-orbit coupling within the singles-singles block is not large.
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