Hi Marks, Thanks for your reply. Let me clarify my question little bit more.
1) I have optimized the slab using mini. 2) I have took this optimized case.struct file from mini calculation, initialized a job for wein2k and run scf calculation. But when I check the force on the same atom here is what I get. case-1: From mini calculation: grep :FGL073 *mini|tail -1 :FGL073: 73.ATOM 0.233000000 0.045500000 4.378500000 total forces case-2: From scf calculation: grep :FGL073 *scf | tail -1 :FGL073: 73.ATOM -1.725500000 -0.171500000 -301.077000000 partial forces My question is why there is difference in force even though in both cases I am using the same structure. In the 2nd case, I have slightly larger RMT and k points. Is it the reason for this difference or I am comparing totally different things. Thanks, Fhokrul Date: Tue, 21 Jun 2011 22:18:38 -0500 From: l-ma...@northwestern.edu To: wien at zeus.theochem.tuwien.ac.at Subject: Re: [Wien] difference in forces from mini and scf calculations You do not provide enough information, so all amyone can do is guess. My guess: you are confusing the valence corrected forces (total at the end of case.scfm) and the uncorrected forces (partial). Mini works with the corrected forces. On Jun 21, 2011 8:40 PM, "Md. Fhokrul Islam" <fislam at hotmail.com> wrote: > > Hi Prof Blaha, > > I optimized a slab using mini and it worked fine (forces on atoms were > reasonably small) . > But when I used the optimized structure from mini calculations and run scf > calculations (with > energy and charge convergence) the forces on atoms increases even after > energy is converged. > So my questions are: > > 1. why forces increases even though I am using exactly the same structure > from mini calculations? > > 2. how does it effect the calculated properties such as DOS, magnetic > moments? I mean should I > trust these numbers that I have calculated from scf calculations? > > I have tried looking for the answer in the mailing list but unfortunately I > couldn't find one. I would > appreciate any comment from you. > > > Thanks, > Fhokrul > > _______________________________________________ Wien mailing list Wien at zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20110622/bb5977bf/attachment.htm>