Relaxation of metal nanowire

Dear All,
i have created metal nanowire and want to apply mechanical loading on it in the form of twisting ans tensile loading at 300 K. I have created it by two means to compare results. FIRST is creating velocity at velocity all create 300.0 4928459 mom yes rot yes and relaxing it through npt for 40ps and SECOND is by velocity all create 1.0 4928459 mom yes rot yes and then increasing temp by 50K in 25ps to reach 300K and then relaxing it through npt for 40ps. Then i am applying loading on these relaxed wires (first and second) using nvt ensemble. My question is
1.Is this right way to get a relaxed wire which may be considered for mechanical loading? if not please correct me…:slight_smile:
2. How can we see that wire is perfectly relaxed?


I have done this for a couple of systems. My comments as follows:

  1. if you claim you are doing simulation of nanowires, no PBC should be used in the lateral dimensions. In that case, NPT is not appropriate or makes no sense. I would use NVT instead. Make sure your simulation box is large enough and no atoms are crossing the box boundaries. That way the surface stress induced axial stress can be released.
  2. Monitor the potential energy, stress of the total system if possible, to see if they are getting to a converged one.


A. J. Cao