Here, q is a vector in the first Brillouin zone, G and G ′ are reciprocal-lattice vectors, ω is frequency, δ is an infinitesimal that locates the poles of χ 0 relative to the real frequency axis, ψ nk and ϵ nk are the Kohn-Sham orbitals and energies from the DFT starting point, and n and n ′ count occupied and empty bands, respectively. See Refs. [38-46] for a detailed review of the GW method. We focus below on the modifications for solvation.