Changing angle potential parameters for a group

LAMMPS LAMMPS General Discussion
1

Dear all,

I would like to change the angle parameters (i.e., the force constant K of harmonic potential “angle_style harmonic”) of a specific group over the course of a simulation. Can LAMMPS do this?

Since this is what exactly fix adapt does, I thought I would start there. However,

fix adapt all adapt 1 angle harmonic k 1 v_ka
fix adapt B adapt 1 angle harmonic k 1 v_ka

give me the exactly the same trajectory. So it seems like fix adapt ignores the group and applies the change globally according to angle type. Is this correct?

Any help would be much appreciated!

Kind regards,

James

2

yes.

You need to request adding an angle type when reading your data file, then change the type of the angles you want to change to that new type and set its parameters accordingly.

3

Thanks for your swift response. I now have a working minimal input file.

Kind regards,

James