Unknown pair style reax/c

Dear friends,

I have got a weird problem here: it says “Unknown pair style (…/force.cpp:190)” to pair_style reax/c". However, the cited code for this error was force.cpp.

I didn’t have any problem before I had reax package installed. And now there is no problem if I don’t use the reax/c command…
If I use pair_style reax command, this error won’t come up but there is an error for open MPI:
ERROR on proc 1: Reax_defs.h setting for NATDEF is too small (…/pair_reax.cpp:284)

I installed reax with the commands listed in documentation:

cd ~/lammps/lib/reax
make -f Makefile.gfortran
cd ~/lammps/src
make yes-reax
make ubuntu

sudo cp lmp_ubuntu /usr/local/bin/

I am using the version of Jul 30, 2016. I ran it with open mpi.
Here is the code I modified from the LAMMPS tutorial for shockwaves:

---------- Initialize Simulation ---------------------

clear
units real #this is required by reaxFF.
dimension 3
boundary p p p
atom_style charge
#atom_modify map array

---------- define variables ---------------------

variable stemperature equal 10 # temperature in kelvin
variable alattice equal 2.855 # lattice constant (unit A)
variable myseed equal 12345 # the value seed for the velocity
variable xmax equal 200 # size in the x-direction
variable ymax equal 30 # size in the y-direction
variable zmax equal 30 # size in the z-direction
variable time_step equal 1 # time step in pico seconds
variable time_eq equal 5000 # time steps for the equlibration part
variable time_shock equal 15000 # time steps for the piston
variable vpiston equal 1.087 # piston speed in (km/s) multiply by ten to obtain (A/ps)
variable Nevery equal 10 # use input values every this many timesteps
variable Nrepeat equal 5 # number of times to use input values for calculating
variable Nfreq equal 100 # calculate averages every this many timesteps
variable deltaz equal 2.855 # thickness of spatial bins in dim (distance units)
variable atomrate equal 250 # the rate in timestep that atoms are dump as CFG
variable tdamp equal “v_time_step100" # DO NOT CHANGE
variable pdamp equal "v_time_step
1000” # DO NOT CHANGE

DO NOT CHANGE

variable Up equal “10000*v_vpiston”
timestep ${time_step}

---------- Create Atoms ---------------------

lattice bcc {alattice} origin 0.0 0.0 0.0 orient x 1 0 0 orient y 0 1 0 orient z 0 0 1 region sim_box block 0 {xmax} 0 {ymax} 0 {zmax} units lattice
create_box 2 sim_box
region atom_box block 0 {xmax} 0 {ymax} 0 ${zmax}
create_atoms 1 region atom_box

define a group for the atom_box region

group atom_box region atom_box
region piston block INF 6 INF INF INF INF
region bulk block 6 INF INF INF INF INF
group piston region piston
group bulk region bulk
set group piston type 1
set group bulk type 2

---------- Define Interatomic Potential ---------------------

print “-------”
pair_style reax/c NULL
pair_coeff * * ffield.reax Fe Fe
mass 1 55.845
mass 2 55.845

------------ Equilibrate ---------------------------------------

reset_timestep 0

Now, assign the initial velocities using Maxwell-Boltzmann distribution

velocity atom_box create {stemperature} {myseed} rot yes dist gaussian
fix equilibration bulk nvt temp {stemperature} {stemperature} ${tdamp} drag 1
thermo 10

thermo_style custom step pxx pyy pzz lx ly lz temp etotal

restart 1000 restart.eq.*
run ${time_eq}

Thank you guys for help.
Best,

Hi Zheng Kang,

reax/c is part of the USER-REAXC package, not reax.

Best,
Thomas