G-K viscosity method,

Dear All users,

I have a problem in viscosity calculation for a system including water(SPC water model). I

performed an NVT(2 ns) simulation in 300 k and 0.997 gr/cm^3 density (at 1 bar pressure). My

simulation box contains 500 water molecules. I get the value average viscosity which is not

consistent with litrature even far from that. Where is my problem?

my MD run: average viscosity: 0.024308852311398083251 Pa.s

From literature: 7.978e-4 Pa.s

This is my input file:

I suggest to check rdf first.

Two notices, I am not sure which type of model is it in the literature. spc is a rigid model; but, you are using a flexible model.

The nvt temp have a very small tdamp.


The reference of bond and angle parameters for SPC is:

Teleman, O.; Jonsson, B.; Engstrom, S. A molecular dynamics
simulation of a water model with intramolecular degrees of freedom.
Mol. Phys. 1987, 60 (1), 193−203.