Dear wien2k users, I am calculating the properties of several f-electron compounds. I would like to ask the users' opinion about the volume optimization in an f- or d-electron system: which way is better (or physically justified), with LDA/GGA or with LDA+U/GGA+U? In my opinion, the LDA+U/GGA+U techniques were developed to correct band energies of localized states, so there is no fundamental physical reason to use LDA+U/GGA+U methods for volume optimization. However, we observe a change in the lattice parameters when we go from LDA/GGA to LDA+U/GGA+U. Also, from a brief search of the literature we found that, in many cases, people tune the Hubbard-U parameter to reproduce the experimental lattice constants. I would appreciate further thoughts and insights into this issue.
Thank you, Zs -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20130301/6e6d398a/attachment.htm>
