Fig. presents similar features of the polariton potential with a cavity frequency of hω c = 9.5 eV. For this case, the photon dressed state |ψ 0 (R), 1⟩ (green curve) hybridizes with the |ψ A 1 2 , 0⟩ (gray) and generate a large Rabi splitting at R = 1.25 Å. Interestingly, due to the light-matter interaction, the middle polariton curve (red curve in R=1.35 Å) in this panel has a lower energy compared to the original adiabatic state |ψ A 1 2 , 0⟩ (gray). The inset shows that the avoided crossing has been reduced to 9 meV, a reduction by an order of magnitude compare to the original avoided crossing in the bare molecule (Fig. ). This is because that the photon-dressed ground state (green) "pushes" down upon the ψ A 1 2 state (due to the light-matter coupling), effectively reducing the magnitude of the avoided crossing. In Supporting Information, we also present the magnitude of the avoided crossing as a function of the cavity energy in Fig. .