Dear lammps users
i am going to simulate oxygen molecules adsorption on single layer graphene. here is my input file:
dimension 3
units real
boundary p p f
atom_style charge
What you observed is absolutely normal since your fix nvt is applied to group all and you used fix momentum. You should not be using fix momentum - what is the purpose of using fix momentum?
Ray
Dear Ray
thanks for your reply, in fact when i did not use fix momentum ,system is drifted during simulation
, so i used this command for subtracting the center-of-mass velocity .
(in this system pressure are too negative values)
Best Regard.
System drifting is a symptom indicating a problem wrong with your setup, structure, force field, etc. I suggest you fix the problem instead of suppress the symptom.
Ray
Dear Ray
why can not i use fix momentum,I've checked different options, but in any case the system moves in z direction , and i have to use this fix.
Best Regard.
On some rare occasions you do have normal net momentum so that you need this fix, but your is not. Your system should not drift in the z direction, and it is possible that you incorrectly assigned initial velocities. I suggest you figure out why your system is moving, instead of using fix momentum to suppress the symptom. Otherwise with that fix, your system will have nothing moving in the z direction.
Ray