Dear experienced Users and developer Wien2k, ? ?Is it possible to use U value for Oxygens with l=1 orbitals. I always get error. Thanks for your response. ? with best regards, Haranath Ghosh
--- On Tue, 6/26/12, shamik chakrabarti <shamikphy at gmail.com> wrote: From: shamik chakrabarti <shamik...@gmail.com> Subject: Re: [Wien] A basic question about GGA+U approach To: "A Mailing list for WIEN2k users" <wien at zeus.theochem.tuwien.ac.at> List-Post: wien@zeus.theochem.tuwien.ac.at Date: Tuesday, June 26, 2012, 6:37 PM Dear Prof. Peter Blaha, ? ? ? ? ? ? Thank you very much for your reply. I got my answer. with best regards, On Tue, Jun 26, 2012 at 11:19 AM, Peter Blaha <pblaha at theochem.tuwien.ac.at> wrote: Yes, U depends on the type of atom, but of course also on the specific compound. For metallic Fe the U should be in the range of 0-2 eV at most, for some insulating compound with very localized states, it may go up to even 4-6 (maybe even 8) eV. Am 26.06.2012 06:42, schrieb shamik chakrabarti: Dear wien2k users, ? ? ? ?We generally choose the value of U by fitting it with experimental band gap or by calculating it through linear response method. Now my question is that whether U is element specific or depends on the composite in which the element reside? (*if I consider same magnetic configuration for all the composites I am referring here...as antiferromagntism do produce a band gap even without applying any U*) To make it more clear, say for Fe d, I have seen in literature, people have used U=4.5 to 5 eV......in some of our calculation we have even used U=6 eV for Fe d to obtain better electronic structure having closer match with experimental observation. Hence it looks that U for Fe d orbital can have value ranging from 4.5-6 eV...& that mean U is not element specific rather it depends on the composite in which the element exist (I again want to insist that if I consider same magnetic configuration for all the composites). Am I right? with regards, -- Shamik Chakrabarti Senior Research Fellow Dept. of Physics & Meteorology Material Processing & Solid State Ionics Lab IIT Kharagpur Kharagpur 721302 INDIA _______________________________________________ Wien mailing list Wien at zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien -- Peter Blaha Inst.Materials Chemistry TU Vienna Getreidemarkt 9 A-1060 Vienna Austria +43-1-5880115671 _______________________________________________ Wien mailing list Wien at zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien -- Shamik Chakrabarti Senior Research Fellow Dept. of Physics & Meteorology Material Processing & Solid State Ionics Lab IIT Kharagpur Kharagpur 721302 INDIA -----Inline Attachment Follows----- _______________________________________________ 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/20120626/1ac3f32d/attachment.htm>