J R J (where µ ′ J = dµ G (R)/dR J ), and we assume that µ M (R M ) = 0. Here, c J is the reactant-solvent coupling constant and ω J is the solvent frequency. For simplicity, we assume that the solvent molecules are identical, such that c J = c s , ω J = ω s and µ ′ J = µ ′ s . Note that these solvent molecules are aligned anisotropically around the reactive molecule. Similar to the previous work in the single-molecule limit, the GH theory can be applied to this system to study the reaction rate suppression due to the cavity mode. However, the suppression will also depend on the solvent frequency ω s and the total number of solvent molecules N . At the dividing surface R M = R ‡ M , the Hessian matrix in the 3-mode x subspace is shown in Eq. 226,