Comparison of thermostatting mechanisms in NVT and NPT simulations of decane under shear

Abstract

Thermostatting mechanisms in NVT and NPT simulations of decane under shear were compared. A thermostat based on configurational expression for the temperature was proposed and applied to nonequilibrium molecular dynamics (NEMD) simulations of decane undergoing Couette flow. Results obtained from this model were compared with those obtained from center of mass (COM) kinetic thermostat. Results showed that in both NPT and NVT simulations, the increase in potential energy of internal modes with increasing shear can only be observed with a Gaussian isokinetic COM thermostat. No such increase was noticed with configurational thermostat and it correctly accounts for internal degrees of freedom of molecular fluid. Show more