  The ion distribution of electrolytes near interfaces with dielectric contrast
has important consequences for electrochemical processes and many other
applications. To date, most studies of such systems have focused on
geometrically simple interfaces, for which dielectric effects are analytically
solvable or computationally tractable. However, all real surfaces display
nontrivial structure at the nanoscale and have, in particular, nonuniform local
curvature. Using a recently developed, highly efficient computational method,
we investigate the effect of surface geometry on ion distribution and interface
polarization. We consider an asymmetric 2:1 electrolyte bounded by a
sinusoidally deformed solid surface. We demonstrate that even when the surface
is neutral, the electrolyte acquires a nonuniform ion density profile near the
surface. This profile is asymmetric and leads to an effective charging of the
surface. We furthermore show that the induced charge is modulated by the local
curvature. The effective charge is opposite in sign to the multivalent ions and
is larger in concave regions of the surface.
