Using the PySCF software, we would generalize DMET in two ways to facilitate the analysis of chromophore-solvent orbital entanglement. The first generalization is for the density matrix in Eq. ( ) to include extra contributions from the lowest n virtual or-Figure : TDA-ωB97X-D/6-311++G(d,p) excitation energies (in eV) within the embedding orbital (eo) basis for the S 1 state of the OLU - (panels A-F) and pHBDI -(panels G-L) anions, both in 30 water molecules. The embedding orbitals were obtained from the P 0 , P +1 , P +2 , P +5 , P +20 , and P max density matrices, respectively, following the DMET scheme. For P max , the number of virtual orbitals added is equal to the number of nearly zero singular values of P AE 0 . The red asterisks indicate the gas-phase excitation energy for each biochromophore. bitals of the chromophore-solvent complex,