(no subject)

Dear All
I performed a NVE simulation of 108 water molecules and after that ran a NVT simulation using the
restart file for 5 ns at 300K, but the temperature seems to be showing the fluctuations which are
large.
I am not sure if I have not committed any mistake. Below is given the input file and the output of
the log file for last few steps.

Created by charmm2lammps v1.6.3 on Fri Mar 30 13:26:53 CDT 2007

dimension 3
units real
boundary p p p

kspace_style ewald 1.0e-4

kspace_modify order 3
atom_style full
pair_style lj/cut/coul/long 7.0
bond_style harmonic
angle_style harmonic
pair_modify mix arithmetic
newton off
read_data water.nvt.lammps
#read_restart xfile.restart.100000
group cat type 1
group ain type 2
group wtr type 1 2
#variable fff equal fx[1]
neighbor 1.0 bin
neigh_modify delay 0 every 1 one 6000
minimize 1.0e-4 1.0e-6 100 1000
fix 1 wtr shake 0.0001 20 0 t 1 2 a 1 b 1

fix 2 all npt temp 300.0 300.0 100.0 iso 1.00 1.00 1000.0 drag 0.3

fix 3 all ave/correlate 100 1 100 v_fff

fix 2 all nvt temp 300.0 300.0 100.0

fix 3 all rdf 10 xwtr.rdf 300 3 3 3 4 4 4 2 3

fix 4 all rdf 10 xion.rdf 300 1 3 1 4 1 2 2 4

compute 1 all rdf 100 1 1 2 2 1 2
timestep 1.0

thermo 1000
thermo_style custom step pe ke etotal temp press vol

restart 50000 z.restart

dump 1 all custom 5000 z.output.dump id type efieldx efieldy efieldz
#dump 2 all custom 5000 z1.output.dump id mol type x y z fx fy fz
run 500000

log file
step pe ke etotal temp press vol

457000 -1045.5334 186.95994 -858.57349 291.72644 1389.022 3369.7017
458000 -1038.2314 195.45206 -842.77936 304.97728 100.79581 3369.7017
459000 -1053.7343 186.20883 -867.52546 290.55443 -314.9359 3369.7017
460000 -1070.2957 185.15925 -885.13649 288.91671 -380.99695 3369.7017
461000 -1076.2393 188.11568 -888.12363 293.52982 600.65651 3369.7017
462000 -1068.5366 212.55498 -855.98159 331.66414 -194.43336 3369.7017
463000 -1074.4526 186.69318 -887.75942 291.3102 1223.036 3369.7017
464000 -1050.9456 182.84322 -868.10241 285.30285 28.734651 3369.7017
465000 -1071.8305 191.73694 -880.09356 299.18032 -77.374807 3369.7017
466000 -1053.0516 197.87144 -855.18018 308.75241 77.998918 3369.7017
467000 -1051.484 182.43352 -869.05052 284.66356 -626.51827 3369.7017
468000 -1035.8778 198.26204 -837.61574 309.36188 1395.6651 3369.7017
469000 -1053.3 184.02608 -869.27394 287.14854 292.96345 3369.7017
470000 -1068.3844 191.44492 -876.93949 298.72467 -597.29209 3369.7017
471000 -1045.2102 204.64723 -840.56298 319.32514 -386.99863 3369.7017
472000 -1053.8886 192.03611 -861.85253 299.64714 -863.58266 3369.7017
473000 -1061.7103 174.7936 -886.91668 272.74246 -519.84226 3369.7017
474000 -1058.8733 187.39579 -871.47746 292.40653 -361.3347 3369.7017
475000 -1066.6326 205.61218 -861.02043 320.83082 1315.4476 3369.7017
476000 -1075.8261 201.67723 -874.14885 314.69084 1703.9622 3369.7017
477000 -1070.3519 186.84502 -883.50687 291.54712 972.19782 3369.7017
478000 -1031.6898 204.99505 -826.69472 319.86787 499.88696 3369.7017
479000 -1064.7511 207.90064 -856.85045 324.40165 743.63421 3369.7017
480000 -1093.329 203.00511 -890.32393 316.76283 -68.718231 3369.7017
481000 -1043.0375 193.57426 -849.46319 302.04722 -483.94126 3369.7017
482000 -1073.2163 155.06286 -918.15344 241.95523 -10.636311 3369.7017
483000 -1085.7257 181.04332 -904.68242 282.49434 -1160.0202 3369.7017
484000 -1088.8772 202.68563 -886.19159 316.26432 -1262.9963 3369.7017
485000 -1047.8148 182.92814 -864.88666 285.43534 634.16247 3369.7017
486000 -1068.1821 203.23418 -864.94789 317.12026 48.256007 3369.7017
487000 -1035.5969 188.57814 -847.01873 294.25143 1981.3918 3369.7017
488000 -1045.4373 196.50393 -848.93341 306.61858 -1288.6414 3369.7017
489000 -1080.4262 184.39826 -896.02791 287.72928 -1131.4833 3369.7017
490000 -1056.531 199.36772 -857.16329 311.08716 -234.94921 3369.7017
491000 -1054.3832 196.02978 -858.35341 305.87874 -941.79329 3369.7017
492000 -1080.8182 200.44777 -880.37045 312.77244 511.39651 3369.7017
493000 -1081.7114 184.998 -896.71337 288.66509 -100.4875 3369.7017
494000 -1072.7665 210.43729 -862.32924 328.35977 530.88522 3369.7017
495000 -1031.0107 208.0277 -822.98302 324.59992 1410.5335 3369.7017
496000 -1070.9307 194.83691 -876.09379 304.01742 1353.0945 3369.7017
497000 -1039.4637 191.65833 -847.80535 299.05766 -1332.7778 3369.7017
498000 -1038.2331 209.74524 -828.48789 327.27991 1197.2403 3369.7017
499000 -1038.5292 186.65204 -851.87716 291.24601 1175.5309 3369.7017
500000 -1052.0844 206.51545 -845.56899 322.24026 1080.6287 3369.7017
500078 -1040.5822 198.19587 -842.3863 309.25864 368.53938 3369.7017

Please guide me about the results.
Thanks
DeepaK Ojha
School Of Chemistry

“Selfishness is not living as one wishes to live, it is asking others to live as one wishes to live”

Dear All
I performed a NVE simulation of 108 water molecules and after that ran a NVT
simulation using the
restart file for 5 ns at 300K, but the temperature seems to be showing the
fluctuations which are
large.

for as tiny a system of ~100 molecules the temperature
fluctuations *have* to be "large".

if you search the mailing list archives, you will find many
people asking the same question and you may find
enlightenment in the resulting discussions.

cheers,
    axel.