Profile-biased thermostat

Galilean invariance is lost due to the coupling of monomers to the heat bath, which mimics a solvent that rests in the laboratory frame. Therefore, the method belongs to the class of profile-biased thermostats [138]. This can be demonstrated easily Let us consider a film of linear polymers confined by two adsorbing substrates. Shear is applied by moving the upper substrate with a constant velocity, w, while the lower... 

The effects of thermostats on the transport properties of simple fluids continue to be explored. In particular the configurational thermostat is studied in NEMD simulations to address a number of shortcomings of previous work that used profile biased kinetic thermostats. Delhommelle et al.242 perform... 

In order to obtain a steady state from Eqs. 38 dissipative heat must be removed from the system. This is achieved by the last (thermostatting) terms of the last two equations in Eqs. 38. In this respect it is essential to observe that accurate values for Uj and A are needed. Any deviations from the assumed streaming and angular velocity profiles (biased profiles) will exert unphysical forces and torques which in turn will affect the shear-induced translational and rotational ordering in the system [209,211,212]. The values for the multipliers and depend on the particular choice of the thermostat. A common choice, also adopted in the work of McWhirter and Patey, is a Gaussian isokinetic thermostat [209] which insures that the kinetic and rotational energies (calculated from the thermal velocities p" and thermal angular velocities ot) - A ) and therefore the temperature are conserved. Other possible choices are the Hoover-Nose or Nose-Hoover-chain thermostats [213-216]. 

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