Hej Zimin, Yes I want to get the q-dependent nesting function, the double delta represented by Gaussians (arXiv:cond-mat/0504077v2) to test it against other methods for the the nesting function as introduced in (PRL 96, 047004 (2006)) and (PHYSICAL REVIEW B 71, 064501 (2005)). We are currently trying to implement inelastic electron-phonon coupling and very good convergence of the double delta is an issue. Furthermore I would be really interested in how you shift the Fermi energy *within the code*. The derivative of the potential is taken at the Fermi energy - is the shifting after scf cycle? It would be great if you could share more details of the Fermi energy shifting. If it's to detailed don't mind to write at my email (nicki.hinsche(at)physik.uni-halle.de).
thanks a lot, Nicki ------------------------------------------------------------- Nicki Frank Hinsche, Dr. rer. nat. Institute of physics - Theoretical physics, Martin-Luther-University Halle-Wittenberg, Von-Seckendorff-Platz 1, Room 1.07 D-06120 Halle/Saale, Germany Tel.: ++49 345 5525460 ------------------------------------------------------------- > Hi Nicki, > > Sorry I didn't quite follow you: as I understand - correct me if I'm > wrong - what you are trying to get is a product of delta > functions(?!). They don't have any relations whatsoever with > electron-phonon interactions. Am I right? If you don't mind, would > you like to tell me why you are tring to get this quantity? > > The shifting of Fermi energy is done by manually adding 0.05 > electrons *within the code*, rather than tot_charge - in the latter > way QE calculates forces and phonons with the charged system. But > the convergence with respect to smearing is done by visual > examination :P - I don't yet know of something that quantifies this > criterion :( > > you are welcome > fzm -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20140202/8bc5b7a5/attachment.html
