Excluding one degree of freedom

Hi everyone
Say if i have a 2D system in y-z plane , and i want the dynamics in this plane only. Can i exclude the motion along x-axis ,x-y plane, and x-z plane.


Yes, you can. First of all, why do not you consider your system in x-y plane and use the 2D setting of lammps which are described in the manual. Second, if you really want to restrict the x motion; you can set velocities and forces equal to 0 in the x direction using set velocity and set force command. This is just a suggestion.


I have defined the system in x-y plane and restricting z motion through:

fix 4 mobile setforce NULL NULL 0.0
#fix 5 mobile momentum 0.5 linear 1 1 0
velocity mobile set NULL NULL 0.0…, but still there is motion in z plane, can you assist further…


run.in.npt (1.81 KB)

See the fix enforce2d command.