Shear viscosity of liquid copper at experimentally accessible shear rates: Application of the transient-time correlation function formalism

We report on nonequilibrium molecular dynamics (NEMD) simulations results on the shear viscosity of liquid copper, modeled by a many-body embedded-atoms model potential. Because conventional NEMD methods are restricted to very high shear rates (at least of the order of 10¹⁰ s^-1, that is several orders of magnitude larger than those accessible by experiment), previous work only provided access to the response of the fluid in the shear-thinning regime. Using the transient-time correlation function formalism, we show how NEMD simulations can be extended to study the rheological properties of liquid copper subjected to low, experimentally accessible, shear rates. Our results provide a full picture of the rheology of the system, in the Newtonian regime as well as in the shear-thinning regime.