[CPMD-list] (no subject)

[Axel Kohlmeyer]

On Fri, 13 Jul 2007, kdong wrote:

KD> Hello CPMD Users,

KD>    I am calculating a liquid system including 416 atoms with period
KD> boundary conditions, the TEMPCONTROL ION is 350.0 and tolerance is
KD> 10.0, the CP molecular dynamics is fine, but when I used the NOSE

can you post a segment of the output displaying the energies
from the tempcontrol part? tempcontrol with a delta of 10.0 
can have too much rescaling and thus hindering equilibration.

KD> thermostat, the CP molecular dynamics was terminated by "Nan" and
KD> could not get the good results, in other words, the NVE is good and
KD> the NVT is not running normally.

how many steps of NVT, what is the time step, fictitious mass,
what platform are you running on etc?? without any detailed 
information or the ability to reproduce this behavior, it is 
impossible to give useful advice.

there may be a lot of reasons to get a NaN output.
quite likely a bad choice of parameters in the input 
or insufficient equilibration. 

cheers,
   axel.

KD>  I can not understand the reasons , can you help me to explain? 

KD>  
KD>   2007-07-13 09:56:47 
KD> 
KD> 
KD> 
KD> K. Dong    
KD> Institute of Process Engineering
KD> Chinese Academy of Sciences (CAS)
KD> Beijing 100080, China
KD> Tel: 86-10-62550850
KD> Mobile: 13811865926
KD> Email: dongkun at home.ipe.ac.cn and kdong_bj at sina.com  
KD> 

-- 
=======================================================================
Axel Kohlmeyer   akohlmey at cmm.chem.upenn.edu   http://www.cmm.upenn.edu
   Center for Molecular Modeling   --   University of Pennsylvania
Department of Chemistry, 231 S.34th Street, Philadelphia, PA 19104-6323
tel: 1-215-898-1582,  fax: 1-215-573-6233,  office-tel: 1-215-898-5425
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If you make something idiot-proof, the universe creates a better idiot.