The examination of water potentials by simulating viscosity

The shear viscosity of liquid water is simulated by molecular-dynamics (MD) method with a variety of nonpolarizable potentials (SPC, MCY, TIPS2 and TIP4P). By comparisons with experimental data, it shows that Stokes–Einstein relation can be used to calculate the viscosity of water. The calculated viscosity is lower than the experimental value at these temperatures bellow 293 K, but it is reasonably agreement with experimental values at temperatures higher than 313 K. The viscous activation energy for the different potential models is also calculated, the results indicate that the MCY potential is in better agreement with the experimental values than the others.