[DFTB-Plus-User] fail to use Nose-Hoove Thermostat

Bálint Aradi balint.aradi at bccms.uni-bremen.de
Mon Sep 10 10:16:41 CEST 2012


Dear Lijuan Meng,

>     I am a new user of DFTB+. I  use  the Nose-Hoove  Thermostat to
> control the system temperature. However, the error " Failure in
> diagonalisation routine dsygvd, non-positive definite overlap!
> Minor      1 responsible."  is present in the log file. The
> structure has been  optimized and computation is normal if other
> thermostat way is applied, which means that the structure used is
> reasonable. I present the input file and corresponding md.out file  in
> the below section. I am looking forward to your help. 

 Hm, that is somewhat strange, especially the NaN-s in the chain
variables. Did you use the binary downloaded from the webpage. If yes,
could you please send me a full input (including geometry and SK-files
you used), so that I can have a look at it?

   Best regards,

  Bálint


> 
> 
> Lijuan Meng
> Southeast University
> 
> 
> 
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Geometry = GenFormat {
>  <<< "am-opt.gen"
>  }
> Driver = VelocityVerlet{
>   MovedAtoms = 1:132
>   Steps = 200000                  
>   TimeStep [Femtosecond] = 0.5      
>   OutputPrefix = "am-2500k"
>   Thermostat = NoseHoover {
>   Temperature [Kelvin] = 2500.0
>   CouplingStrength = 500.0
>  }
>  # Velocities  = {
>  #<<< "VELOC.DAT"
>  #}
> MDRestartFrequency = 1
> }
> Hamiltonian = DFTB {
>   SCC = Yes
>   SCCTolerance = 1.0e-4
>   MaxSCCIterations = 200
>   Mixer = Broyden {}
>   Eigensolver = DivideAndConquer {}
>   MaxAngularMomentum = {
>     C = p
>     Ni = d
>   }
>   Charge = 0.000
>   Filling = Fermi {
>     Temperature [Kelvin] = 10000
>   }
>   SlaterKosterFiles = {
>     C-C = "C-C.skf"
>     C-Ni = "C-Ni.skf"
>     Ni-C = "Ni-C.skf" 
>     Ni-Ni = "Ni-Ni.skf"
>   }
>    KPointsAndWeights = SupercellFolding{
>      1 0 0
>      0 1 0
>      0 0 1
>      0.0 0.0 0.0
>   }
> }
> 
> Options = {
> RandomSeed = 0
> WriteDetailedOut = No
> WriteBandOut = No
> }
> 
> ParserOptions = {
>   ParserVersion = 4
> }
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> md.out
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>  MD step:           0
>  Nose-Hoover chain variables
>  x:
>     0.1000000000E+01    0.1000000000E+01    0.1000000000E+01
>  v:
>     0.0000000000E+00    0.0000000000E+00    0.0000000000E+00
>  g:
>     0.0000000000E+00    0.0000000000E+00    0.0000000000E+00
>  Pressure:                          -0.102769E-04 au    -0.302358E+09 Pa
>  Potential Energy:                -229.3775402846 H        -6241.6804 eV
>  MD Kinetic Energy:                  1.5556980384 H           42.3327 eV
>  Total MD Energy:                 -227.8218422463 H        -6199.3477 eV
>  MD Temperature:                     0.0079170384 au        2500.0000 K
>  MD step:           1
>  Nose-Hoover chain variables
>  x:
>                  NaN                 NaN                 NaN
>  v:
>                  NaN                 NaN                 NaN
>  g:
>                  NaN                 NaN                 NaN
>  Pressure:                                    NaN au              NaN Pa
>  Potential Energy:                -229.3640994512 H        -6241.3147 eV
>  MD Kinetic Energy:                           NaN H               NaN eV
>  Total MD Energy:                             NaN H               NaN eV
>  MD Temperature:                              NaN au              NaN K
>  MD step:           2
>  Nose-Hoover chain variables
>  x:
>                  NaN                 NaN                 NaN
>  v:
>                  NaN                 NaN                 NaN
>  g:
>                  NaN                 NaN                 NaN
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> 
> 
> This body part will be downloaded on demand.
> 


-- 
Dr. Bálint Aradi
Bremen Center for Computational Materials Science, University of Bremen
http://www.bccms.uni-bremen.de/cms/people/b_aradi/


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 259 bytes
Desc: OpenPGP digital signature
URL: <http://www.dftb-plus.info/pipermail/dftb-plus-user/attachments/20120910/104f829c/attachment.pgp>


More information about the DFTB-Plus-User mailing list