(185r) Self-Consistent Thermostatting of Molecular Dynamics Simulation In the Presence of Inhomogeneous, Non-Equilibrium Fields through Multiscale Modeling

Spatially inhomogeneous non-equilibrium fields can give rise to non-uniform generation of heat. Molecular dynamics simulations performed in the presence of inhomogeneous, non-equilibrium fields therefore require thermostatting capable of adding or removing energy with spatial selectivity. If the field is not isotropic, it is also necessary to decouple the thermostats for each dimension of the system. In this work, we demonstrate that a thermostatting scheme with both spatial and dimensional selectivity is capable of generating a uniform temperature profile in the presence of an anisotropic and spatially inhomogeneous non-equilibrium field. We show that the resulting density profile is consistent with both a molecular-level theoretical prediction from statistical mechanics as well as the solution of the continuum-level set of differential equations describing the conservation of mass and momentum. Finally, we show that for fluids with non-negligible intermolecular interactions, the continuum-level description requires a mechanical equation of state generated by the molecular dynamics simulation in order to provide consistent results.