Dear all,
I’m using reax/c to simulate Al oxidation. I previously used ‘fix deposit’ command but I kept getting segmentation fault error. On this mailing list I was suggested that reaxFF might not be able to handle changing number of atoms in the system. Then I tried constant number of oxygens with random positions, and single O2 molecule, but nothing works again.The only thing that I noticed is that if I deposit Al on Al substrate then it seems OK. Based on that I thought there is something with charges and I also tried ‘checkqeq no’, doesn’t help either. I’m sure reaxFF should handle this but I’m run out of options what else to try.
Could anyone have a look at my in.file or at least check if it works for others (I’m running March 5, 2012 parallel version of lammps) - all files attached.
#---------- initialize -------------
log sdep.log
dimension 3
units real
boundary p p p
atom_modify map array sort 0 2.0
atom_style charge
#----------- geometry --------------
lattice fcc 4.05
region box block 0 10 0 10 0 18
region substrate block 0 10 0 10 2 10
region deposit block 0 10 0 10 10 18
region bottom block 0 10 0 10 2 4
create_box 2 box
create_atoms 1 region substrate # Al substrate
mass 1 26.98
mass 2 16.0
group freeze region bottom # constrain bottom 2 layers
#---------------------------------------settings--------------------------------------------------------
neighbor 2.5 bin
neigh_modify every 10 delay 0 check no
pair_style reax/c al_control # checkqeq no
pair_coeff * * ffield.reax.Al 7 3
fix 1 all qeq/reax 1 0.0 10.0 1.0e-6 reax/c
fix 4 freeze setforce 0.0 0.0 0.0
run 0
#----------------- add oxygens --------------------------------
#---------- 10 atoms with random positions --------------------------------------
create_atoms 2 random 10 2346 deposit
#--------------------- O2 ---------------------------------------
#create_atoms 2 single 18 22 50 units box
#create_atoms 2 single 19.21 22 50 units box
group oxygens type 2
velocity all create 300.0 2436254 dist gaussian
velocity oxygens set NULL NULL -0.002 units box
fix 7 all npt temp 300.0 300.0 100.0 iso 0.0 0.0 100.0
dump o_info oxygens custom 10 vel.xyz id vx vy vz x y z q
thermo_style custom step temp etotal press atoms
thermo_modify lost warn
thermo 50
timestep 0.1
run 10000
Thanks for any help,
Manana Koberidze
in.sdep (1.43 KB)
ffield.reax.Al (21.7 KB)
al_control (513 Bytes)