How to delete and generate a molecule on a surface in LAMMPS?

Dear LAMMPS users,

I am trying to model an electrochemical reaction (O2 + 4H+ + 4e- = 2H2O) by LAMMPS artificially. It means that I want to consider H2O and O2 in the reaction. Since the reaction happens on the catalyst surface, I want to write a LAMMPS input file in which 1. oxygens get disappeared on the catalyst surface 2. The disappeared oxygen molecules enter the simulation box.
I would be grateful if there are any suggestions.

Thanks,
Atefeh

Perhaps fix bond/react can do what you want. Otherwise, you would need to look into writing your own fix that will remove atoms/molecules and replace with other atoms/molecules. There are fix evaporate and fix deposit that can each do half of it, so there is some kind of template to follow.

Hi,

Thank you so much for your response.
I have a couple of questions.

  1. Does the fix bond/react command needs a reactive force field?
  2. I have not written my own fix so far; is there any guidance for it?

Thanks,
Atefeh

No. On the contrary.

There is a whole section in LAMMPS manual about modifying and extending LAMMPS.