[CPMD-list] effect of fictitious electron mass

[Axel Kohlmeyer]

On Wed, 23 Apr 2008, Yun-an Yan wrote:

YY> 
YY> Dear all,
YY> 
YY> I use the default value for Fictitious Electron Mass (EMASS)
YY> to optimize a system with Gromacs/CPMM. Later on I change
YY> the value to 800 a.u. instead of 400 a.u. but got the same energy.
YY> I am confused. EMASS should have some effects, shouldn't it?
YY> 

yun-an,

the Gromacs/CPMD QM/MM interface does not do any 
Car-Parrinello dynamics. you'll always be doing 
BO-dynamics. thus the fictitious mass will _never_ 
have an impact. if you want to see how the fictitious 
mass impacts CP-dynamics, i suggest to look at 
the examples at http://www.theochem.rub.de/go/cpmd-tutor.html

cheers,
   axel.

YY> Thank you so much for your consideration.
YY> 
YY> Best wishes,
YY> Yun-an Yan
YY> _______________________________________________
YY> CPMD-list mailing list
YY> CPMD-list at cpmd.org
YY> http://cpmd.org/mailman/listinfo/cpmd-list
YY> 

-- 
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Axel Kohlmeyer   akohlmey at cmm.chem.upenn.edu   http://www.cmm.upenn.edu
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