[lammps-users] would you please help me about water simulation in LAMMPS?

Dear Friends,

I want to simulate TIP3P model of water. I run a dynamics after minimization (In minimization step at first I run 1000 dynamic steps and then I use 'fix minimize command). Then I use ‘fix shake’ to apply bond and angle constraints of water molecules in npt ensemble and run 6000 dynamic steps with ‘run command’. I apply 20,200,2000 number of iteration parameter, but I receive the following warning and error at the initial step of dynamic steps with ‘run command’ . Also after minimization with ‘fix nve’ the temperatures and pressures of the system increase to infinite values. Should I change which parameter or data to remove these problems.
Is it possible help me about this.

WARNING: One or more atoms are time integrated more than once
ERROR: Out of range atoms - cannot compute PPPM

Memory usage per processor = 98.6459 Mbytes
Step Temp E_pair E_mol TotEng Press
0 2910 -0.082491071 16.005727 4327.0343 47.323904
100 1800.2055 -0.025017784 1653.5776 4320.5237 5.7634274
200 1985.9562 -0.042891363 1384.499 4326.6134 11.568816
300 2054.6698 -0.036793026 1289.6754 4333.5939 14.402265
400 1932.6632 -0.023276196 1478.1905 4341.372 9.7514089
500 2035.0203 0.012465273 1330.2831 4345.1404 13.66415
600 2096.6231 -0.017391122 1243.1125 4349.2034 15.953035
700 2065.9419 -0.026152417 1288.012 4348.6404 14.473534
800 1883.6376 -0.035160831 1562.6827 4353.2218 8.2233982
900 2126.4166 0.63138012 1200.5612 4351.4394 17.000599
1000 2106.8089 -0.030028417 1237.0772 4358.2454 15.847865
Loop time of 521.965 on 1 procs for 1000 steps with 81 atoms

Pair time () = 0.032862 (0.00629582) Bond time () = 0.019788 (0.00379106)
Kspce time () = 521.797 (99.9678) Neigh time () = 0.067948 (0.0130177)
Comm time () = 0.025673 (0.00491853) Outpt time () = 0.002694 (0.000516127)
Other time (%) = 0.018916 (0.003624)

FFT time (% of Kspce) = 423.874 (81.2335)
FFT Gflps 3d (1d only) = 0.46434 1.2658

Nlocal: 81 ave 81 max 81 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Nghost: 131 ave 131 max 131 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Neighs: 118 ave 118 max 118 min
Histogram: 1 0 0 0 0 0 0 0 0 0

Total # of neighbors = 118
Ave neighs/atom = 1.45679
Ave special neighs/atom = 2
Neighbor list builds = 1000
Dangerous builds = 0
PPPM initialization …
G vector = 1.33726
grid = 90 90 90
stencil order = 5
RMS precision = 7.83149e-07
brick FFT buffer size/proc = 912673 729000 112908
Setting up minimization …
Memory usage per processor = 99.5688 Mbytes
Step Temp E_pair E_mol TotEng Press
1000 2106.8089 -0.030028417 1237.0772 4358.2454 15.847865
1050 2106.8089 -0.003050736 0.00046253749 3121.1957 34.305408
1098 2106.8089 -3.1919031e+12 0.019356644 -3.1919031e+12 -1.5976964e+10
Loop time of 371.202 on 1 procs for 98 steps with 81 atoms

Minimization stats:
Stopping criterion = linesearch alpha is zero
Energy initial, next-to-last, final =
1237.04713824 -3.19190306604e+12 -3.19190306604e+12
Force two-norm initial, final = 19456.9 2.74447e+29
Force max component initial, final = 4631.17 1.29375e+29
Final line search alpha, max atom move = 9.30397e-66 1.20371e-36
Iterations, force evaluations = 98 715

Pair time () = 0.031719 (0.00854494) Bond time () = 0.016476 (0.00443855)
Kspce time () = 371.13 (99.9805) Neigh time () = 0.001337 (0.000360181)
Comm time () = 0.009063 (0.00244153) Outpt time () = 0.000715 (0.000192617)
Other time (%) = 0.013225 (0.00356275)

FFT time (% of Kspce) = 41.5168 (11.1866)
FFT Gflps 3d (1d only) = 0.464596 1.25836

Nlocal: 81 ave 81 max 81 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Nghost: 116 ave 116 max 116 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Neighs: 143 ave 143 max 143 min
Histogram: 1 0 0 0 0 0 0 0 0 0

Total # of neighbors = 143
Ave neighs/atom = 1.76543
Ave special neighs/atom = 2
Neighbor list builds = 20
Dangerous builds = 0
Finding SHAKE clusters …
0 = # of size 2 clusters
0 = # of size 3 clusters
0 = # of size 4 clusters
27 = # of frozen angles
PPPM initialization …
G vector = 1.33726
grid = 90 90 90
stencil order = 5
RMS precision = 7.83149e-07
brick FFT buffer size/proc = 912673 729000 112908
WARNING: One or more atoms are time integrated more than once
Setting up run …
SHAKE stats (type/ave/delta) on step 1098
1 0.958852 0.0547633
1 103.976 6.67795
Memory usage per processor = 100.306 Mbytes
Step Temp E_pair E_mol TotEng Press Volume
1098 3180.0888 -3.1919031e+12 0 -3.1919031e+12 nan 4913
ERROR: Out of range atoms - cannot compute PPPM