A flow chart for the RAS-SF + PCM algorithm is illustrated in Fig. , including both the nonequilibrium ptSS and the state-relaxed equilibrium procedure. The algorithm begins by computing the RAS-SF ground state wave function in the gas phase. Next, one-electron integrals are modified to incorporate R0 and the groundstate total energy is iterated to convergence, as in any SCRF calculation except that the lowest eigenstate of a CI Hamiltonian must be computed at each SCRF iteration. This completes step 1 in Fig. . Once the groundstate eigenfunction has been equilibrated with respect to the medium, excited states (including LE and/or CT states, as desired) are obtained by computing additional eigenstates in the presence of a fixed reaction-field operator R0 . These are the zeroth-order states |Ψ Step 1 of the ptSS approach involves an SCRF calculation using the ground-state eigenvector of the CI Hamiltonian (illustrated with a gray box, as in Fig. ). In step 2, excited-state eigenvectors are computed from the CI Hamiltonian using a frozen reaction field for the ground state ( R0), then corrected using the perturbation Rf k -Rf 0 . In this approach, all of the CI eigenvectors can be corrected at once and only a single CI calculation is required in step 2. Alternatively, the fully-relaxed equilibrium procedure corresponds to a SCRF calculation in the presence of reaction-field Rk , solving the state-specific Schrödinger equation [Eq. ( )] one state at a time to obtain fully-relaxed energies E k .