I am trying to do structure relaxation and energy minimization by using Reax, eam and meam poetntials for nanorods (you can see input and data files in attachment).
Before I did both relaxation and minimization for very similar kind structures but for this I am not getting any results, its still running even after 30 hours.
What could be wrong?
I would really apperciate your comments/suggestions.
Thanks!
about structure relaxation
I dont know how this commands works, but in our programs of the MD, I create a box (constant volume) and vacuum around the nanowire or nanorod. And change "made by hand" the box size seeing stress value evolution, and periodically set velocity to zero, kind five times per box size change. Another idea is to use langevin thermostat to remove oscillations of the system.
"vibrating like guitar string"
this idea probably would have given an article at the time of my PhD. but that was how to stop the pendulum with the hands. :)
I added this by mistake but I dont think so it causes any problem. The problem in my openion is to choose correct tolerance value.
about structure relaxation
I dont know how this commands works, but in our programs of the MD, I create a box (constant volume) and vacuum around the nanowire or nanorod. And change "made by hand" the box size seeing stress value evolution, and periodically set velocity to zero, kind five times per box size change. Another idea is to use langevin thermostat to remove oscillations of the system.
"vibrating like guitar string"
this idea probably would have given an article at the time of my PhD. but that was how to stop the pendulum with the hands. :)
Hi Zhang,
Yes, I already tried minimization in lammps and it worked for nanorod.
Thanks!
Sometimes minimization can take very long time.
but you can use fix 1 nve/limit 0.01
which won't let the system to explode for an equilibration
Dear All,
I have a similar question on relaxation after dynamic run for few time steps. I am twisting a beam for some time steps and relaxing the system to settle using Minimization command (I am using LAMMPs).Using the following commands of LAMMPs:
min_style cg
minimize 1.0e-4 1.0e-6 1000 1000
The system is under NVT ensemble with non-periodic BCs. If I do minimization for longer time the system returns to the original configuration and the net twist is zero. If I adjust the parameters of minimization command, the system deforms well, but the results do not match with literature (I mean I get higher regime of elastic deformation).
Can anyone give some input on this or suggest an alternative to relax the system after dynamic run.
Thanks a Lot...I really appreciate ...!
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