A question about bond/create/break fixes

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1

Dear LAMMPS experts

My name is Sasha, I use LAMMPS for adhesion simulation. I have a melt of long polymers mixed with short crosslinker. I generate the initial state with pizza.py tool, then gradually "charge up" lj interactions. Then I need to do a DYNAMICAL chemical equilibrium of the crosslinker with the polymer and bump into a problem.

I do include

2 extra bond per atom in the read_data file

special bond lj extra 100 in the script file

fix bond/create every 500 steps with the new bond type and the probability of bond creation
fix bond/breake every 100 steps with the bond type and the proability of bond breaking

What hapens is that the simulator creates bonds only ones, and the bond/breake breaks them. That bonds that a broken a newer creted again and there is no chemical equilibrium.

However, if I write a restart file and load ot, the bonds are created again(although the counter is set to zero at the beginning)

So my questin is :HOW TO MAKE THE DYNAMICAL CHEMICAL EQUILIBRIUM WORK?

Thank you very much or your time
I would greatly appreciate your help

2

I don't know. Most people use either fix bond/create or fix bond/break,
but not both at the same time. I don't see why it wouldn't be possible
to run them both as competing fixes, so long as they are both operating
very slowly.

Steve