Dear Mr. Unknown, it depends on the system you are treating. Each individual phonon mode costs roughly as much as a single ground-state calculation. So, the total cost scale as (number of atoms) * (cost of a ground-state calc), i.e. of the orther of the fourth power of the numbr of atoms ...
Also, please do not forget to sign your posts - that practice is very much appreciated by this community. Cheers - Stefano Baroni On Nov 15, 2007, at 6:36 AM, shoutian sun wrote: > > I calculate phonons with ph.x. It cost me more than a week, some > even two > > months. > > could anyone tell me that is mormal? > > Thank you. > > > > @yahoo.cn ????????????? > _______________________________________________ > 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 [+39] 040 3787 406 (tel) -528 (fax) / stefanobaroni (skype) 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/20071116/bc1608bd/attachment.htm
