restraining atoms on z-axis

Dear Users

I’m new to LAMMPS and I want to carry out a simulation which involves restraining the motion of some atoms in z-direction while allowing them to move on x and y axis. can we do that on lammps. I would greatly appreciate if can help with this. Please

thanks

Milinda Samaraweera
University of Connecticut
Department of Chemistry
55 N Eagleville road
unit 3060
Storrs CT
USA

Dear Users

I’m new to LAMMPS and I want to carry out a simulation which involves restraining the motion of some atoms in z-direction while allowing them to move on x and y axis. can we do that on lammps. I would greatly appreciate if can help with this. Please

thanks

Milinda Samaraweera
University of Connecticut
Department of Chemistry
55 N Eagleville road
unit 3060
Storrs CT
USA

Try the Fix setforce command.

Freddie.

Dear Users

I'm new to LAMMPS and I want to carry out a simulation which involves
restraining the motion of some atoms in z-direction while allowing them to
move on x and y axis. can we do that on lammps. I would greatly appreciate
if can help with this. Please

please be more precise: do you want to apply a restraining force in
z direction (i.e. atoms would be allowed to move in z-direction, but
pull back by the force) or do you want those atoms not to move
in z-direction at all. the answer for how to implement this would be
different.

axel

Hi Axel

I want to fix the atoms in z directions that means no movement is allowed.
and have 592 atoms how do I fix selected number of atoms. do I have to
define a group? if so how to do it

thanks

Milinda Samaraweera
University of Connecticut
Department of Chemistry
55 N Eagleville road
unit 3060
Storrs CT
USA

Define a group of the selected number of atoms.
set the z component of the velocity of the group to zero
use setforce command with NULL NULL 0 setting.

Regards,

Thanks alot vikas

best

Milinda Samaraweera
University of Connecticut
Department of Chemistry
55 N Eagleville road
unit 3060
Storrs CT
USA

You can also look at the fix planeforce command.

Steve