Dear Vijay Khanal Many pages should be written to explain why the simplified linear-response DFT+U formulation is not quite suitable for strongly hybridized sp3 materials like silicon or diamond... If you only want to practice around with the U correction you can (carefully) make your way through this tutorial (download the "correlated materials" files)
http://www.fisica.uniud.it/~giannozz/QE-Tutorial/ Read also Himmetoglu, B.; Floris, A.; de Gironcoli, S.; Cococcioni, M. Hubbard-Corrected DFT Energy Functionals: The LDA+U Description of Correlated Systems. Int. J. Quantum Chem. 2014, 114, 14. If you also want to try to understand why DFT+U is not suitable for Si, then you should start (for example) with these papers: Leiria Campo Jr, V. and Cococcioni, M. Extended DFT + U + V method with on-site and inter-site electronic interactions. J. Phys.: Condens. Matter 22 (2010) 055602 Cohen, A. J.; Mori-Sànchez, P.; Yang, W. Insights into Current Limitations of Density Functional Theory. Science 2008, 321, 792-794. Luis A. Agapito, Stefano Curtarolo, and Marco Buongiorno Nardelli Reformulation of DFT+U as a Pseudohybrid Hubbard Density Functional for Accelerated Materials Discovery. PHYSICAL REVIEW X 5, 011006 (2015) HTH Giuseppe On Wednesday, April 27, 2016 11:30:06 PM Vijay Khanal wrote: > Dear Everyone, > > I am new to Quantum Espresso. I am trying to see how hybrid functionals > better estimate the bandgap of a semiconductor like Silicon. I was > wondering, therefore, if somebody could provide me with demo input/output > files that involve Hubbard's Correction. > > Any response would be highly appreciated. > > > Thank you. > > Respectfully, > Vijay Khanal > *Vijay Khanal* > Department of Physics > University of Nevada, Reno > Phone:(1-*775-440-7036)* ******************************************************** - Article premier - Les hommes naissent et demeurent libres et égaux en droits. Les distinctions sociales ne peuvent être fondées que sur l'utilité commune - Article 2 - Le but de toute association politique est la conservation des droits naturels et imprescriptibles de l'homme. Ces droits sont la liberté, la propriété, la sûreté et la résistance à l'oppression. ******************************************************** Giuseppe Mattioli CNR - ISTITUTO DI STRUTTURA DELLA MATERIA v. Salaria Km 29,300 - C.P. 10 I 00015 - Monterotondo Stazione (RM), Italy Tel + 39 06 90672836 - Fax +39 06 90672316 E-mail: <[email protected]> http://www.ism.cnr.it/en/staff/giuseppe-mattioli/ ResearcherID: F-6308-2012 _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
