To account for nonadiabatic transitions, SHARC uses the Tully's fewest switches surface hopping method , which is a mixed quantum-classical method that propagates nuclei classically according to Newton's equation of motion on different excited-state potentials, which are treated by means of electronic structure theory. Nonadiabatic transitions between different PESs are accounted for by so-called hops across different PESs. These are determined stochastically based on the magnitude of the NACs, which are referred to as C ij in the following and are defined as