Further, λ is the reorganization energy, due to the exciton-phonon coupling, where the diabatic exci-tation energy between the two states is hω x = E e -E g (and throughout the work, we will set h = 1) for all n ∈ [0, N -1] molecules. Each molecule contains a set of phonon vibrations. The phonon DOFs of the molecules are considered as the bath Hamiltonian, which couple to the system through the system-bath (exciton-phonon) coupling, expressed as follows (c.f. Eq. 2)