where ϵ 0 is the permittivity inside the cavity, and V is the effective quantization volume of that mode. For simplicity, we have assumed that the dipole operators are linear such that μ(Q j ) • ê⊥ ≈ Qj • cos φ j , where ê⊥ is the transverse field polarization direction. In contrast to the R 0 -Q j interaction characterized by C j (electrostatic interactions) which depends on the solute-solvent distance, the cavity mode, on the other hand, interacts with all solvent modes {Q j } with η c weighted by cos φ j , resulting in delocalized interactions that can be observed from the Rabi splitting from spectroscopy .