lammps-error

Dear all
I generated a pdb file for 256 water molecules using packmol (attached herewith). That pdb file i used to generate lammps data file using topotools 1.2. But when I run lammps it is comming out with the

LAMMPS (18 Jan 2011)

SPC/E water box benchmark

units real

atom_style full

boundary p p p

read_data data.256water

2 = max bonds/atom

1 = max angles/atom

orthogonal box = (0.02645 0.02645 0.02641) to (35.5328 35.5328 35.4736)

2 by 2 by 1 processor grid

768 atoms

512 bonds

256 angles

2 = max # of 1-2 neighbors

1 = max # of 1-3 neighbors

1 = max # of 1-4 neighbors

2 = max # of special neighbors

#replicate 2 4 1

pair_style lj/cut/coul/long 9.8 9.8

kspace_style pppm 1.0e-4

kspace_modify order 3

pair_coeff 1 1 0.15535 3.166

pair_coeff * 2 0.0000 0.0000

bond_style harmonic

angle_style harmonic

dihedral_style none

improper_style none

bond_coeff 1 1000.00 1.000

angle_coeff 1 100.0 109.47

special_bonds lj/coul 0.0 0.0 0.5

2 = max # of 1-2 neighbors

1 = max # of 1-3 neighbors

1 = max # of 1-4 neighbors

2 = max # of special neighbors

neighbor 2.0 bin

neigh_modify every 1 delay 10 check yes

fix 1 all shake 0.0001 20 0 b 1 a 1

0 = # of size 2 clusters

0 = # of size 3 clusters

0 = # of size 4 clusters

256 = # of frozen angles

fix 2 all nvt temp 300.0 300.0 100.0

velocity all create 300 432567 dist uniform

timestep 2.0

thermo_style one

thermo 50

run 100

PPPM initialization …

G vector = 0.246379

grid = 24 24 24

stencil order = 3

RMS precision = 8.83199e-05

brick FFT buffer size/proc = 8381 3456 4437

Memory usage per processor = 4.3544 Mbytes

Step Temp E_pair E_mol TotEng Press

0 300 15204.218 0 15661.176 139366.74

ERROR: Out of range atoms - cannot compute PPPM

.
Can u please suggest how to overcome it?
Suggestion will be appriciated.
Regards
MALI

data.256water (53.8 KB)

in.256water (684 Bytes)

log.lammps (1.56 KB)

Dear all
I generated a pdb file for 256 water molecules using packmol (attached
herewith). That pdb file i used to generate lammps data file using topotools
1.2. But when I run lammps it is comming out with the

LAMMPS (18 Jan 2011)

# SPC/E water box benchmark

units real

atom_style full

boundary p p p

read_data data.256water

2 = max bonds/atom

1 = max angles/atom

orthogonal box = (0.02645 0.02645 0.02641) to (35.5328 35.5328 35.4736)

2 by 2 by 1 processor grid

768 atoms

512 bonds

256 angles

2 = max # of 1-2 neighbors

1 = max # of 1-3 neighbors

1 = max # of 1-4 neighbors

2 = max # of special neighbors

#replicate 2 4 1

pair_style lj/cut/coul/long 9.8 9.8

kspace_style pppm 1.0e-4

kspace_modify order 3

pair_coeff 1 1 0.15535 3.166

pair_coeff * 2 0.0000 0.0000

bond_style harmonic

angle_style harmonic

dihedral_style none

improper_style none

bond_coeff 1 1000.00 1.000

angle_coeff 1 100.0 109.47

special_bonds lj/coul 0.0 0.0 0.5

2 = max # of 1-2 neighbors

1 = max # of 1-3 neighbors

1 = max # of 1-4 neighbors

2 = max # of special neighbors

neighbor 2.0 bin

neigh_modify every 1 delay 10 check yes

fix 1 all shake 0.0001 20 0 b 1 a 1

0 = # of size 2 clusters

0 = # of size 3 clusters

0 = # of size 4 clusters

256 = # of frozen angles

fix 2 all nvt temp 300.0 300.0 100.0

velocity all create 300 432567 dist uniform

timestep 2.0

thermo_style one

thermo 50

run 100

PPPM initialization ...

G vector = 0.246379

grid = 24 24 24

stencil order = 3

RMS precision = 8.83199e-05

brick FFT buffer size/proc = 8381 3456 4437

Memory usage per processor = 4.3544 Mbytes

Step Temp E_pair E_mol TotEng Press

0 300 15204.218 0 15661.176 139366.74

ERROR: Out of range atoms - cannot compute PPPM

.
Can u please suggest how to overcome it?

you have bad starting geometry.
see the high positive potential energy.

have you read the documentation?
there is a section dedicated to explaining
these kind of problems. also search through
the mailing list archives for previous discussions
on the same subject.

you will have to carefully equilibrate
your system, e.g. through repeated
quenching (via minimize) and running
at a shorter time step until you can
run a production calculation. your cannot
just generate some coordinates with a
tool like packmol and then start production.

have you talked to somebody in your
institution with practical experience in
running MD. if you not, you should urgently
do so.

axel.