Dear lammps-users,
I’m trying to simulate the stretching for diamond nanowires, first I minimize the structure, and then temperature relaxation to 300K, but when stretched along Z, there is an error for floating point exception and the following is the in file. Another question is why the Lx and Ly is also increase instead of decreasing?
#This is the log. File#
LAMMPS (9 Jan 2009)
units metal
boundary s s s
atom_style atomic
dimension 3
#Atom definition
read_data data.CH
orthogonal box = (-1.09707 -1.09707 13.1701) to (11.6799 11.6799 398.112)
1 by 2 by 32 processor grid
13700 atoms
pair_style airebo 3.0 0 0
pair_coeff * * CH.airebo C H
neighbor 2.0 nsq
neigh_modify delay 0 every 10 check yes page 100000
region 2 block INF INF INF INF INF 48.7669 units box
group left region 2
1246 atoms in group left
region 3 block INF INF INF INF 362.4 INF units box
group right region 3
1287 atoms in group right
group middle subtract all left right
11167 atoms in group middle
velocity left set 0.0 0.0 0.0 units box
fix 4 left setforce NULL NULL 0.0
velocity right set 0.0 0.0 0.0 units box
fix 5 right setforce NULL NULL 0.0
minimize 1.0e-6 1.0e-6 1000 100000
Memory usage per processor = 2.72927 Mbytes
Step Temp E_pair E_mol TotEng Press Volume
0 0 -60837.918 0 -60837.918 88008.548 62842.152
252 0 -73509.805 0 -73509.805 -65338.965 85839.623
Loop time of 424.325 on 64 procs for 252 steps with 13700 atoms
Minimization stats:
Stopping criterion = energy tolerance
Energy initial, next-to-last, final =
-60837.9182901 -73509.750813 -73509.8045783
Force two-norm initial, final = 706.347 4.66326
Force max component initial, final = 15.017 1.72312
Final line search alpha, max atom move = 0.0050467 0.00869608
Iterations, force evaluations = 252 524
velocity middle create 600.0 4928459 dist gaussian units box
fix 1 all nvt 300 300 100 drag 0.2
compute myTemp middle temp
thermo_style custom step temp etotal
thermo_modify lost warn flush yes
thermo 500
timestep 0.0005
run 50000
Memory usage per processor = 2.02649 Mbytes
Step Temp TotEng
252 489.0576 -72643.813
500 265.6557 -72639.757
1000 271.89835 -72639.552
…
50000 288.23934 -72609.464
50252 291.30806 -72609.205
unfix 1
fix 1 all nvt 300 300 100
run 50000
Memory usage per processor = 2.50336 Mbytes
Step Temp TotEng
50252 291.30806 -72609.205
50500 292.35759 -72608.989
…
100000 300.14503 -72573.819
100252 300.12216 -72573.53
unfix 1
unfix 5
fix 1 all nve
velocity right set 0.0 0.0 0.0003 units box
velocity middle ramp vz 0.0 0.0003 z 3.5667 103.4343 sum yes units box
compute s middle stress/atom
compute strea middle reduce sum c_s[1]
variable stressa equal c_strea/vol
compute streb middle reduce sum c_s[2]
variable stressb equal c_streb/vol
compute strec middle reduce sum c_s[3]
variable stressc equal c_strec/vol
thermo_style custom step c_myTemp etotal pe press v_stressa v_stressb v_stressc vol lx ly lz
thermo_modify lost warn flush yes
run 500000
Memory usage per processor = 2.59091 Mbytes
Step myTemp stressc Volume Lx Ly Lz
100252 326.51092 0.048937861 2.6429595e+11 7292.3672 7908.463 4582.7893
101000 362.50276 0.03799822 2.707081e+11 7318.2076 7952.266 4651.635
102000 448.37422 0.017477795 2.7940256e+11 7352.7889 8010.8067 4743.5342
srun: error: req727: task52: Floating point exception
srun: Terminating job
Please anybody have idea of such problems? Or there are some wrong in my in.file? I would be very thankful.
Sincerely yours,
Jing