This charge penetration extends only to the first two atomic layers of the gold. On average, the first (skin) layer of metal maintains a small negative charge density, which is largely a response to the solvent environment in closest proximity to the interface. That is, when one of the water hydrogens points at the surface, the local response is a net negative polarization of the adjacent surface gold atoms. The metallic layer below this largely reacts with a net positive charge density, conserving total charge in the metal, and effectively neutralizing local fields at sites internal to the metal structure. In the original work parameterizing DR-EAM, this behavior was also observed in layered metallic structures responding to a uniform electric field. The gold atoms in the spherical nanoparticles respond to nearby atoms with a significantly larger magnitude of charge density. The surface atoms in the nanospheres have fewer metallic neighbors which can spread out the polarization response, and are in contact with a larger solid angle of the solvent. The polarization response directly increases the interaction strength with nearby polar solvent molecules, so the larger interfacial conductance in these systems is not surprising.