Continuum solvation model for ab initio molecular dynamics simulations

In electronic structure calculations, a polarizable solvent can be represented as a continuous homogeneous dielectric. In most models, the value of the dielectric presents a discontinuity at the solute-solvent interface. For first principles pseudopotential DFT calculations based on plane waves or real-space discretization, such an approach is impractical. We present a continuum solvation model in which the electrostatic effects of the solvent are described by a Poisson equation with a smooth continuous dielectric function depending on the electronic density only. This equation is discretized on a grid by finite differences and is solved iteratively by multigrid. This model does not introduce any ionic forces depending explicitly on the molecular cavities and is thus appropriate for geometry optimizations and molecular dynamics simulations.