ZnO thin film simulation

Hi,

I needed to simulate a ZnO thin film and was suggested to used ffield.reax.ZnOH potential for it as the potential energies for Zn-O, Zn-Zn and O-O are already mentioned there.
However I am getting an error

step1-hbondchk failed: H=1 end(H)=55 str(H+1)=50

during the simulation.

I have pasted my log file here. Can anyone please help me with the appropriate potential to be used while simulating ZnO films.

dimension 3
boundary p p s
atom_style charge
units metal
neigh_modify delay 5

read_data ZnO.data
orthogonal box = (-3.8227 -5.51759 0) to (3.8227 2.20704 6.2607)
1 by 1 by 1 processor grid
37 atoms
37 velocities
replicate 5 5 5
WARNING: Replicating in a non-periodic dimension
orthogonal box = (-3.8227 -5.51759 -0.0001) to (34.4043 33.1056 31.3044)
1 by 1 by 1 processor grid
4625 atoms
mass 1 65.34
mass 2 15.999
region mainblock block -20 20 -20 20 -30 0 units box

pair_style reax/c lmp_control
pair_coeff * * ffield.reax.ZnOH 1 2

region bottomface block INF INF INF INF INF -25 units box
group lower region bottomface
0 atoms in group lower
group mobile subtract all lower
4625 atoms in group mobile
set group lower type 2
0 settings made for type

fix freeze lower setforce 0.0 0.0 0.0

fix 2 all qeq/reax 1 0.0 10.0 1e-6 param.qeq
thermo 10
dump dumpxyz1 all custom 10 dump.xyz type x y z
minimize 1.0e-6 1.0e-6 1000 1000
WARNING: Resetting reneighboring criteria during minimization
Memory usage per processor = 36.5605 Mbytes
Step Temp E_pair E_mol TotEng Press Volume
0 0 nan 0 nan nan 46219.44

This is a Q for Aidan.

Steve

Hi,

I needed to simulate a ZnO thin film and was suggested to used
ffield.reax.ZnOH potential for it as the potential energies for Zn-O, Zn-Zn
and O-O are already mentioned there.
However I am getting an error

step1-hbondchk failed: H=1 end(H)=55 str(H+1)=50

during the simulation.

I have pasted my log file here. Can anyone please help me with the
appropriate potential to be used while simulating ZnO films.

dimension 3
boundary p p s
atom_style charge
units metal

aren't the reax potential files parameterized for "real" units and not "metal"?

axel.

Amrita,

I’d be happy to take a look if you send me the input, data, lmp_control and param.qeq files.
Ray

It might be due to a bas geometry, overlapping atoms, etc. Try running
something simpler and/or check the gemoetry with a different potential, or
pair_style reax. if all that fails, send me a simple example.