a problem about lammps

I has a big problem when I simulate an alumina particle with reaxff. I find the particle will move automatically and I cannot control the position of the particle. Also the calculation speed of the computer will be much slower.

The input file is shown below:

REAX potential for AlO particle system

units real # A,fs,K

variable T equal 600

variable V equal vol

variable dt equal 0.5 # fs

variable d equal 10000

set up the geometric model

dimension 3

boundary m m m

atom_style charge

read_data data.Al2O3_d3nm

potential

pair_style reax/c lmp_control

pair_coeff * * ffield.reax.AlAlO 3 7

timestep ${dt}

thermo $d

neighbor 2 bin

neigh_modify every 10 delay 0 check no

velocity all create $T 102486 mom yes rot yes dist gaussian

equilibrium

fix NVT all nvt temp $T $T 8.0 drag 0.2

fix QeQ all qeq/reax 100 0.0 10.0 1e-6 reax/c

restart 100000 restart.*.AlOd3nm_nvt

run 500000

write_restart AlOd3nm_nvt.restart

I has a big problem when I simulate an alumina particle with reaxff. I find
the particle will move automatically and I cannot control the position of
the particle. Also the calculation speed of the computer will be much
slower.

Why shouldn't it move? What are you doing to control it that doesn't work?
Slow compared to what?

Steve