  Solid-liquid interfaces are at the heart of many modern-day technologies and
provide a challenge to many materials simulation methods. A realistic
first-principles computational study of such systems entails the inclusion of
solvent effects. In this work we implement an implicit solvation model that has
a firm theoretical foundation into the widely used density-functional code
VASP. The implicit solvation model follows the framework of joint density
functional theory. We describe the framework, our algorithm and implementation,
and benchmarks for small molecular systems. We apply the solvation model to
study the surface energies of different facets of semiconducting and metallic
nanocrystals and the S$_{\text{N}} 2$ reaction pathway. We find that solvation
reduces the surface energies of the nanocrystals, especially for the
semiconducting ones and increases the energy barrier of the S$_{\text{N}} 2$
reaction.
