Hi, > I did the calculation with ibrav = 1 and 8 atoms
In order to reduce atoms number involved in AFM calculations for B1 type structure (FeO, NiO) you can use basis vectors and atomic positions from run_example file from example25 Bests, Eyvaz. ------------------------------------------------------------------- Prof. Eyvaz Isaev, Department of Physics, Chemistry, and Biology (IFM), Linkoping University, Sweden Theoretical Physics Department, Moscow State Institute of Steel & Alloys, Russia, isaev at ifm.liu.se, eyvaz_isaev at yahoo.com ________________________________ From: mohnish pandey <[email protected]> To: PWSCF Forum <pw_forum at pwscf.org> Sent: Thu, January 13, 2011 2:11:29 PM Subject: Re: [Pw_forum] anti-ferromagnetic calculations Dear Padmaja! As I am using the latest version of QE(i.e 4.2) the 'nelup' and "neldw" variables are no longer there anymore. For magnetic calculations starting with some initial magnetization i.e. starting_magnetization(i). In my experience with AF calculations you should have even number of atoms in the unitcell( unless the system is frustrated or something like that). I did the calculation for NiO which have rocksalt structure so there will be 2 atoms in the unit cell with ibrav = 2. But with this I was not able to hit the ground state because there was only one Ni. So the number mag/unitcell was not zero. But when I did the calculation with ibrav = 1 and 8 atoms the total magnetization~0 and I am able to reach the ground state. And as also Shrubha pointed out that you must do Lowdin analysis to see the magnetization and check the up and down spins. I hope it helps. On Thu, Jan 13, 2011 at 11:25 AM, Padmaja Patnaik <padmaja_patnaik at yahoo.co.uk> wrote: Dear All > >For an anti-ferromagnetic calculation to run in QE which of the following way >is >more correct. >1. specify different values of starting magnetization for different atoms in >the >compound. I mean one positive and one negative value. > >2. specifying the nelup and neldown. > >Thanks and regards >Padmaja Patnaik >Research Scholar >Dept of Physics >IIT Bombay >Mumbai, India > >_______________________________________________ >Pw_forum mailing list >Pw_forum at pwscf.org >http://www.democritos.it/mailman/listinfo/pw_forum > > -- Regards, MOHNISH, ----------------------------------------------------------------- Mohnish Pandey Y6927262,5th Year dual degree student, Department of Chemical Engineering, IIT KANPUR, UP, INDIA ----------------------------------------------------------------- -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110114/1d63af9c/attachment.htm
