Fig. 5.

Natural logarithms of the ratios of τ₀/τ₁ vs. −ΔG⁰/λ (negative Gibbs free energy of reaction in the unit of reorganization energy) corresponding to the results in SI Appendix, Figs. S1.1–S1.3. The term “Classical” refers to the classical limit of Ohmic bath, SI Appendix, Eq. 18, with parameters for SI Appendix, Fig. S1.1. The term “Quantum-1” refers to the quantum regime of the Ohmic bath with parameters for SI Appendix, Fig. S1.2. The term “Quantum-2” refers to the case of classical Ohmic bath plus one quantum mode in the bath with parameters for SI Appendix, Fig. S1.3. Each column represents a different value of ħω_O/λ, where ω_O is the angular frequency of the odorant oscillator and λ is the reorganization energy of the protein environments. S_O = 0.01 (Upper) and S_O = 0.05 (Lower), where S_O is the Huang–Rhys factor for the odorant oscillator.