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 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20120626/b4875214/attachment.htm>