In the γ-SQC approach, it was proposed that the mapping ZPE should be chosen in such a way as to constrain the initial force to be composed purely of the initially occupied state. The basic logic of γ-SQC is to choose a γ b for each state |b⟩ in every given individual trajectory, such that the initial population is forced to respect the initial electronic excitation focused onto a single excited state. If the initial electronic state is |a⟩, then