Total magnetic moment is always zero for any AFM cases due to the cancelation of existed atomic magnetic moments in the unit cell. Total magnetic moment is also zero for any NM cases, but here none of the atoms in the unit cell have magnetic moments. Therefore, total energies can be different for a case in its AFM and NM phases. This is due to the different magnetic orderings of the atoms in the cell, which results in different total energies.
Sincerely yours, S. Jalali /_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ Saeid Jalali Asadabadi, Department of Physics, Faculty of Science, University of Isfahan (UI), Hezar Gerib Avenue, 81744 Isfahan, Iran. Phones: Dep. of Phys. :+98-0311-793 2435 Office :+98-0311-793 4176 Fax No. :+98-0311-793 2409 E-mail :sjalali at phys.ui.ac.ir Homepage :HYPERLINK "http://sci.ui.ac.ir/~sjalali"http://sci.ui.ac.ir/~sjalali www :HYPERLINK "http://www.ui.ac.ir"http://www.ui.ac.ir /_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ From: [email protected] [mailto:wien-bounces at zeus.theochem.tuwien.ac.at] On Behalf Of John Appleton Sent: Wednesday, June 25, 2008 2:48 AM To: wien at zeus.theochem.tuwien.ac.at Subject: [Wien] Magnetic moments Dear users, I performed LDA+U bulk calculations for antiferromagnetic (AFM) and non-magnetic (NM) cells. As outlined in the user guide, the NM calculations were run as spin-polarized but the moments were constrained to zero using runsp_c_lapw. After optimization, the total magnetic moment (spin+orbital) for the AFM cell is zero, implying that it is non-magnetic. However compared to the NM cell, the AFM cell has a lower total energy. Is that possible? If the initial AFM cell has a total moment of zero after optimization, then I expect it to have a total energy that is quite close to the NM cell. I would like to state that the lattice constants of the two cells are quite close. Could the magnetization axis be the problem? The default [001] direction was used. No virus found in this incoming message. Checked by AVG. Version: 7.5.524 / Virus Database: 270.4.1/1516 - Release Date: 6/24/2008 7:53 AM No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 270.4.1/1516 - Release Date: 6/24/2008 7:53 AM -------------- next part -------------- An HTML attachment was scrubbed... URL: http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20080625/e1ca08ba/attachment.html
