coupling parameters in nphug

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1

Hello,

I’ve run the test example located in the nphug directory of the constant stress hugoniostat method.
In the original paper of this method by Ravello et al (2004) they claim that the proper choice of the ergostat heat flow coupling parameter and the strain rate coupling parameter is very important when one likes to reproduce NEMD temperature-volume-pressure relations, otherwise the results are more characteristic of an isentropic compression.

However, none of these parameters are available in the lammps implementation. Am I wrong ?
If not, how should I consider these parameters in order to have meaningful results with this method ?

I’ve checked the source code, yet didn’t see any section about these coupling parameters…
The only adjustable parameter is the drag factor for the thermostat and barostat, which doesn’t seem to be the one’s Ravello’s talking about.

Best Regards,

2

Aidan can probably answer this.

Steve

3

The coupling parameters are linearly related to the temperature and
pressure damping parameters required by fix nphug.

4

Thanks for your reply, Aidan

Could you please tell me Where I can find this relation of pressure and
temperature damping parameters and the specific coupling constants ?
How exactly are they related ?

Best,
Dave