Reverse nonequilibrium molecular dynamics RNEMD

There are NEMD schemes where cause and effect are reversed the flux is imposed and the corresponding field is measured. Gonceptually this approach is based on the theorems of Norton and Thevenin which are an example of the macroscopic duality that exists between what are generally recognized as thermodynamic fluxes and thermodynamic forces. The principle of reverse perturbation has been used by Miiller-Plathe for calculating the shear viscosity, thermal conductivity, Soret coefficients, and thermal diffusion. For example, in the calculation of shear viscosity, the reverse nonequilibrium molecular dynamics (rNEMD) method involves a simple exchange of particle momenta the effect, the... 

An alternative NEMD method has been developed that is much simpler to implement than is the SLLOD method, particularly for charged systems such as ionic liquids. The method is called reverse nonequilibrium molecular dynamics (RNEMD) and was first developed as a means for computing thermal conductivity but has also been applied to viscosity. It differs from conventional equilibrium and nonequilibrium methods where the cause is an imposed shear rate and the measured effect is a momentum flux/stress. RNEMD does the opposite it imposes the difficult to compute quantity (the momentum flux or stress) and measures the easy to compute property (the shear rate or velocity profile). The method is very simple to implement because it only requires periodic swapping of momenta between atoms at different positions in the box. These swaps set up a velocity profile in the system (i.e., a shear rate). By tracking the frequency and amount of momentum... 

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