  We report a comprehensive study of aqueous halide adsorption on nanoparticles
of gold and palladium that addresses several limitations hampering the use of
atomistic modeling as a tool for understanding and improving wet-chemical
synthesis and related applications. A combination of thermodynamic modeling
with density functional theory (DFT) calculations and experimental data is used
to predict equilibrium shapes of halide-covered nanoparticles as a function of
the chemical environment. To ensure realistic and experimentally relevant
results, we account for solvent effects and include a large set of vicinal
surfaces, several adsorbate coverages as well as decahedral particles. While
the observed stabilization is not significant enough to result in thermodynamic
stability of anisotropic shapes such as nanocubes, non-uniformity in the halide
coverage indicates the possibility of obtaining such shapes as kinetic
products. With regard to technical challenges, we show that inclusion of
surface-solvent interactions lead to qualitative changes in the predicted
shape. Furthermore, accounting for non-local interactions on the functional
level yields a more accurate description of surface systems.
