[CPMD-list] NAN trajectory for 32 water simulation

Alexandr Isayev alex at ccmsi.us
Mon Dec 10 20:02:35 UTC 2007


Dear Chang,

Just couple of remarks:

1. Your time step (7 au) is too high, even if you replace hydrogen by
deuterium. BTW, did you replace hydrogens at all? I do not see this
section in your input. Time step around 5 au will be more realistic.

2. If you following cpmd list, please always pay attention to the
Axel's remarks :) For instance, restating his last reply:
do you really need thermostat on electrons? Where did you get value
0.04.  On my memory, this value is for 64 water molecules. You can not
just just take it.

3. The other possible source of NANs can be improper restarting and/or
corrupted restart file, poor geometry, etc. Without looking to results
is hard to say more.

Sincerely,
Alexandr


Sunday, December 9, 2007, 10:11:30 PM, you wrote:

CYW> Dear CPMD users, 

CYW> I'm running CPMD with 32 water for a test case. 
CYW> I get NAN in TRAJEC.xyz for my water simulation. I found some
CYW> posting about NAN problem in the CPMD mailing-list. My case is little different. Now I'm
CYW> trying to follow published work: JCP 120, 300 (2004). Since the
CYW> paper didn't specify temperature coupling, I took Nose-hoover parameters from JPCB 108,
CYW> 12990 (2004). 
CYW> I don't know why I'm getting NAN. 

CYW> Please help me if anyone knows.  Thanks a lot in advance!

CYW> Chang 
CYW> Here is my input file. 

CYW> &CPMD
CYW>   MOLECULAR DYNAMICS CP
CYW>   RESTART WAVEFUNCTION COORDINATES LATEST
CYW>   TRAJECTORY XYZ 
CYW>   TEMPERATURE
CYW>   300
CYW>   TIMESTEP 
CYW>   7.0 
CYW>   MAXSTEP 
CYW>   100 
CYW>   EMASS
CYW>    760
CYW>   NOSE IONS
CYW>   298 2000
CYW>   NOSE ELECTRONS
CYW>   0.04 10000
CYW> &END

CYW> &DFT
CYW>   FUNCTIONAL BLYP
CYW> &END

CYW> &SYSTEM
CYW>   SYMMETRY
CYW>   1
CYW>   CELL
CYW>   18.6251  1.0  1.0  0  0  0
CYW>   CUTOFF
CYW>   80.0
CYW> &END

CYW> &ATOMS
CYW> *O_GO_BLYP.psp  KLEINMAN-BYLANDER
CYW>    LMAX=P
CYW>  32 
CYW>   0.3590     6.9542     12.2265 
CYW>   2.8157     13.2848     13.5493 
CYW>   12.9446     0.4913     12.5667 
CYW>   11.4517     18.2170     2.3244 
CYW>   11.3006     13.7761     5.1023 
CYW>   0.0945     7.7479     4.8377 
CYW>   1.0393     13.2470     8.1069 
CYW>   10.3935     3.7039     16.7241 
CYW>   7.2188     13.2281     9.0707 
CYW>   17.4233     9.5053     16.9886 
CYW>   10.1856     1.2094     9.6754 
CYW>   10.6014     4.1952     3.0425 
CYW>   13.3226     1.2094     6.9542 
CYW>   10.6958     10.1478     16.3461 
CYW>   4.2141     9.9211     5.1967 
CYW>   13.8328     11.9809     1.4740 
CYW>   5.8015     1.1905     11.6785 
CYW>   0.6992     14.4753     18.2548 
CYW>   6.0282     15.3068     17.9335 
CYW>   6.4062     9.6187     0.3779 
CYW>   15.4013     10.8092     6.1416 
CYW>   8.9384     9.4486     3.6094 
CYW>   5.9715     16.1572     5.8393 
CYW>   1.5685     5.1401     0.6803 
CYW>   17.0642     1.6252     2.5133 
CYW>   4.9700     6.1605     13.6060 
CYW>   17.3099     17.1965     5.4991 
CYW>   1.3606     3.1369     6.0093 
CYW>   4.5164     6.1416     8.4849 
CYW>   11.2250     14.0785     12.3210 
CYW>   16.2327     18.0658     16.2705 
CYW>   8.0880     8.0124     9.8266 
CYW> *H_MT_BLYP.psp 
CYW>    LMAX=S
CYW>   64 
CYW>   -1.1905     7.7668     12.9635 
CYW>   -0.1701     5.5747     11.0360 
CYW>   3.8928     14.7588     13.0769 
CYW>   1.6819     13.7761     14.9855 
CYW>   14.2485     0.1890     13.8895 
CYW>   11.5651     1.5685     13.2848 
CYW>   11.5840     19.8043     1.3039 
CYW>   12.3210     18.4626     3.9873 
CYW>   11.7541     15.0800     3.8172 
CYW>   9.8266     14.3997     6.1227 
CYW>   -1.3606     8.3904     5.8582 
CYW>   -0.5480     6.7841     3.3448 
CYW>   1.5307     13.1714     9.9211 
CYW>   -0.5669     12.2832     7.8424 
CYW>   10.2990     3.6094     18.6138 
CYW>   10.4313     5.5180     16.1761 
CYW>   8.0691     11.5273     9.0140 
CYW>   5.4424     13.0202     9.6943 
CYW>   16.9508     9.3352     15.1745 
CYW>   18.3303     7.9557     17.5745 
CYW>   8.6549     1.2283     10.7714 
CYW>   10.2423     2.7779     8.6360 
CYW>   11.3195     2.6078     3.7417 
CYW>   8.9384     4.5542     3.8739 
CYW>   13.0580     1.3417     8.8250 
CYW>   14.9099     0.2457     6.6140 
CYW>   10.9226     11.3950     14.9477 
CYW>   11.5651     10.7903     17.9146 
CYW>   4.4598     8.3337     6.2172 
CYW>   3.6661     11.3195     6.3306 
CYW>   14.9477     11.4895     0.0378 
CYW>   13.3037     13.7950     1.2661 
CYW>   5.5936     2.9669     12.3021 
CYW>   5.7070     0.0000     13.1336 
CYW>   0.9827     14.8721     20.0689 
CYW>   0.1323     12.6801     18.0847 
CYW>   7.7857     15.9871     18.0280 
CYW>   5.9148     13.7005     18.9162 
CYW>   5.4235     8.0502     0.0567 
CYW>   7.8613     9.7132     -0.8315 
CYW>   15.5335     9.1274     5.2723 
CYW>   13.6249     11.4517     5.9904 
CYW>   10.0911     10.9604     3.6850 
CYW>   7.1432     10.0344     3.7417 
CYW>   4.3464     15.5713     6.6329 
CYW>   5.8959     15.8926     3.9684 
CYW>   1.4740     5.1212     2.5700 
CYW>   0.0000     4.3653     -0.0378 
CYW>   18.0280     1.6441     0.8882 
CYW>   18.1225     0.8315     3.8550 
CYW>   3.4771     7.1243     12.9635 
CYW>   4.7999     5.8770     15.4580 
CYW>   18.5004     17.9146     4.2141 
CYW>   18.0658     15.6280     6.2361 
CYW>   1.0393     4.7054     4.9889 
CYW>   3.0614     2.4377     5.5936 
CYW>   5.7448     4.7432     8.2770 
CYW>   4.8944     7.0865     10.0722 
CYW>   12.1698     15.6847     11.9620 
CYW>   9.5620     14.1163     11.4139 
CYW>   17.2532     16.7619     17.1776 
CYW>   15.6280     19.3697     17.5178 
CYW>   8.6549     6.6518     8.6549 
CYW>   7.3510     7.2565     11.3950 
CYW> &END


CYW> Chang Yeon Won
CYW> -------------------------------------------------------------------------
CYW> Grad. Res. Asst. (Ph.D Candidate)
CYW> Computational MEMS/Nano Lab
CYW> 3213 Beckman Institute 
CYW> University of Illinois at Urbana-Champaign    
CYW> 405 N. Mathews Avenue
CYW> Urbana, IL 61801                            Office (217)244-1964
CYW> -------------------------------------------------------------------------
CYW> _______________________________________________
CYW> CPMD-list mailing list
CYW> CPMD-list at cpmd.org
CYW> http://cpmd.org/mailman/listinfo/cpmd-list



-------------------------------------------------------
Alexandr Isayev,
Graduate Research Assistant, and System Administrator
@ Computational Center for Molecular Structure
and Interactions (CCMSI),
Jackson State University,
Jackson, MS USA
   Tel:  +(601) 979-1134
e-mail:  alex(at)ccmsi.us
   Web:  http://www.ccmsi.us
--------------------------------------------------------



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