[lammps-users] nanowire tensile

Hi, all

I want to make tensile test of nanowire at finite temperature. One end is clamped, while the other end is displaced. The command “fix nvt” is used to equilibrate the nanowire.After some period, the temperature of system oscilates about the target temperature, but the magnitude of pressure oscilation is large(some hundred bars). Is this state of nanowire a stress-free state? Start from this state, should I tensile the nanowire for further simulations?

Thanks in advance.

hi, Cheng,

What kind of materials are you simulating? what do you mean " After some period, the temperature of system oscilates about the target temperature" ?

Usually, temp should get closer to the target temp after some time running and the oscilating magnitude should be reduced. “fix NVT”, in my opinion, is not a good one to relax a nanowire to a stress-free state if you use a periodic boundary condition in the axis direction, because the length of wires is setted accoording to the bulk lattice constant. If it is non-periodic in the length direction, it is fine and hundred bars oscilation is also possible.

Best,

AC