Hi lammps users,
Is there any way to implement "fix command " something in “molecule id” style not the “group id” style? Just like the form:
fix ID molecule ID style args
The reason is because I have 50 molecule in the box, and I want them to be vibrational equilibrium (by removing translational and rotational velocities of each molecule). To do this, I can do following operation:
group group_1 molecule 1
group group_2 molecule 2
group group_50 molecule 50
fix 1 group_1 momentum 100 linear 1 1 1 angular
fix 2 group_2 momentum 100 linear 1 1 1 angular
fix 50 group_50 momentum 100 linear 1 1 1 angular
Then, each of molecule’s translational and rotational velocities will be removed. However, there is a limit (32) for group numbers, and I know it is very difficult to extend max group number after search on LAMMPS Mailing Archives.
I am wondering if I can only fix is in molecule ID style by LAMMPS or by minor changes? Or I can do this with other way?Otherwise I should write a total new fix, with will difficult without using “group” class.
Thank you in advance.