I want to give rotational energy to a molecule

We are trying to see the interaction between two ions and a neutral molecule at some distance.
I want to give rotational energy to the whole molecule, but it doesn’t work. Is there any solution?
The following method does not work because the atoms in the molecule rotate on their own.

set group mol1 omega 1 0 0

mol1 is the molecule we want to rotate. Atomstyle is hybrid charge and sphere.


LAMMPS has no commands that operate on molecules as such. The set command would take the group as a selector, but would then operate on the individual atoms. Thus to induce the desired change to the system, you would have to manually compute which values of atomic velocities you would need to apply to each individual atom and then set those individually for each atom with “set atom” commands.

Dr. akohlmey

Thank you very much. I will try to use the “set atom” commands as you suggested. I may ask again.