HOW to add reaxff forcefield to cellulose built with cellulose builder

[arnaud KT]

Hello,

i am trying to add a reaxff force field to cellulose struture i built using cellulose structure. I use LAMMPS August-2023 version. I tried adding this forcefield by performing a  simulation in lammps where i added reaxff pair_style and force field file; ffield.reax and ran the simulation in an npt ensemble for equilibration. Visualising this simulation on VMD shows a complete mix up of atoms and species.log file indicate numerous species formed.

 Please, how can i add reaxff force field into the cellulose structure i built ?

Below are the input script, cellulose data file and the force field file .