too short a time step? SB On Dec 5, 2009, at 4:37 AM, mohnish pandey wrote:
> Dear users ! > I tried to calculate bulk energy and equilibrium lattice > parameters of some system using vc-relax calculation. I done the calculation > using both the algorithm naming (1)damped dynamics means 'ion_dynamics' as > "damp" and 'cell_dynamics' as "damp-w" (2) BFGS means 'ion_dynamics' as > "bfgs" and 'cell_dynamics' as"bfgs" . I have changed only these two things > in these two alogorithm. But first case was taking very much time(~2hours) > and wasnt convergence after 200 ionic steps whereas in the second case it > took very less time (6-7 minutes) to get equilbrium bulk structure. Can > anybody please explain me what is the thing which is making so much differnce? > Sincere thanks in advance, > Mohnish > > -- > Mohnish Pandey > Y6262,4th Year Undergraduate, > Department of Chemical Engineering, > IIT KANPUR > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum --- Stefano Baroni - SISSA & DEMOCRITOS National Simulation Center - Trieste http://stefano.baroni.me [+39] 040 3787 406 (tel) -528 (fax) / stefanobaroni (skype) La morale est une logique de l'action comme la logique est une morale de la pens?e - Jean Piaget Please, if possible, don't send me MS Word or PowerPoint attachments Why? See: http://www.gnu.org/philosophy/no-word-attachments.html -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20091205/b62d5e50/attachment.htm
