where E U,V ≡ ⟨V U,V ⟩ 1 corresponds to the solute-solvent potential energy averaged with respect to the fully (solute-solvent) coupled statistics (i.e. λ = 1), and ∆E V ≡ ⟨V V ⟩ 1 -⟨V V ⟩ 0 is the "solvent reorganization energy," which quantifies the change in the solventsolvent energy due to restructuring the solvent around the fully coupled solute relative to the structure and solvent-solvent energies of the pure solvent. Similarly, ∆E U ≡ ⟨V U ⟩ 1 -⟨V U ⟩ 0 quantifies the change in the solute (internal) potential energy in the fully-coupled system relative to that of the ideal gas solute. We will refer to the sum, ∆E V +∆E U , as the total reorganization energy.