Considering that the ground vibronic state of reactant (𝜅 = 0) is the dominant state (𝑃 / =1), the contribution from the excited vibrational states of reactant (𝑃 *2/ ) can be neglected. A recent literature report showed that a certain 𝜈 state tended to dominate in the contribution to the rate constant , then Eq. S8 can be simplified to: