[lammps-users] concerning tdamp

In my previous simulation, I find that the thermodynamic properties such as potential energy has correlation with the choices of tdamp.different choices will produce different quantitative thermodynamic output,which is is unexpected,how to avoid this? How to choose tdamp so as to give best prediction of the simulation system? thanks in advance.

ChenJi
Material Science And Engineering Department
Xi’An Technological University
Xi’An,ShanXi Province,710032
P.R.C.

2009/9/2 limitworld <[email protected]>:

In my previous simulation, I find that the thermodynamic properties such as
potential energy has correlation with the choices of tdamp.different choices
will produce different quantitative thermodynamic output,which is is
unexpected,how to avoid this? How to choose tdamp so as to give best

it is more likely that the problem is elsewhere and that
using a short damping time is hiding it. this is a well
known risk of using thermostatting. run the same system
with NVE ensemble and see how well it conserves energy,
if it doesn't, then you have to adjust your simulation parameters
so it does or find out what is creating a non-equilibrium environment.

a second, less likely, reason could be that your system is not
fully equilibrated or your data acquisition time is too small, so
that your statistical errors are larger than the systematic changes.

cheers,
    axel.