Hello Shafat,
thank you for your answer !!!
The phenomenon I am observing is really quick, when I performed the simulations in the NPT ensemble it took just 100 000 dt to the system to evolve (my system is a perfect crystal with a circular grain disoriented in the middle, I am studying grain boundary motion driven by curbature … the system is heated and the round grain in the center reduces its size, till the system turns in a perfect crystal.). I have to admit that the system is really small.
Anyway, I run just 50 000 steps because I was worry about this wild fluctuations of pressure, so I said ‘let’s fix this before perfoming full simulations’. The initial configuration at t = 0 is previously relaxed at the desired simulation temperature.
I will try also to use the ‘fix temp/resclae’, and follow your advices.
In any case, I was wondering if the Langevin thermostat is a good thermostat for condensed matter, I am not able to clearly visualize the physical meaning of gamma in this case.
Thank you once more,
Carolina
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