Simulation of charged systems in heterogeneous dielectric media via a true energy functional.
For charged systems in heterogeneous dielectric media, a key obstacle for molecular dynamics (MD) simulations is the need to solve the Poisson equation in the media. This obstacle can be bypassed using MD methods that treat the local polarization charge density as a dynamic variable, but such approaches require access to a true free energy functional, one that evaluates to the equilibrium electrostatic energy at its minimum. In this Letter, we derive the needed functional. As an application, we develop a Car-Parrinello MD method for the simulation of free charges present near a spherical emulsion droplet separating two immiscible liquids with different dielectric constants. Our results show the presence of nonmonotonic ionic profiles in the dielectric with a lower dielectric constant.
Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA.
Vikram
V
Jadhao
Francisco J
FJ
Solis
Monica
M
Olvera de la Cruz
D004563:Electrochemistry / Q000379:methods*; D004655:Emulsions / Q000737:chemistry; D007700:Kinetics; D056004:Molecular Dynamics Simulation; D055672:Static Electricity; D013816:Thermodynamics
D004655:Emulsions