Did you check how the Brillouin zone looks like in the tetragonal case after you applied the strain ? Is your k-path that you used for the xmgrace plot the one that you like to have to find the correct gap ?
Ciao Gerhard DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy: "I think the problem, to be quite honest with you, is that you have never actually known what the question is." ==================================== Dr. Gerhard H. Fecher Institut of Inorganic and Analytical Chemistry Johannes Gutenberg - University 55099 Mainz and Max Planck Institute for Chemical Physics of Solids 01187 Dresden ________________________________________ Von: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at] im Auftrag von Muhammad Sajjad [sajja...@gmail.com] Gesendet: Donnerstag, 10. Dezember 2015 09:19 An: A Mailing list for WIEN2k users Betreff: Re: [Wien] Correct band gap value Manually means I opened the band structure in xmgrace then simply clicked on the CBM and the went to the text editor to read the exact lowest value. I am simply using Silicon (with 2% strain) and the plot is along W L G X W. On Thu, Dec 10, 2015 at 10:35 AM, <t...@theochem.tuwien.ac.at<mailto:t...@theochem.tuwien.ac.at>> wrote: What does "manually" mean? If it means band structure plotting, then probably the VBM and/or CBM is not along the path in the Brillouin zone that you chose. F. Tran On Thu, 10 Dec 2015, Muhammad Sajjad wrote: I selected 2000 k-points. grep GAP *.scf gives 0.923 eV while manually I found VBM at 0.0 eV and CBM at 1.10023 eV. So which one should be correct? On Thu, Dec 10, 2015 at 12:20 AM, <t...@theochem.tuwien.ac.at<mailto:t...@theochem.tuwien.ac.at>> wrote: If your k-mesh is not dense enough such that there is no k-point at the VBM and/or CBM or close to, then :GAP will be larger than the band gap from a band structure. F. Tran On Wed, 9 Dec 2015, Muhammad Sajjad wrote: Dear AllDoes the command "grep GAP *.scf" gives correct band gap value? as when I found the bottom of conduction band in xmgrace it is higher. (bottom of CB is read correctly by opening the plot in xmgrace and then read the date by editing in text editor). -- Kind Regards Muhammad Sajjad Post Doctoral Fellow KAUST, KSA. _______________________________________________ Wien mailing list Wien@zeus.theochem.tuwien.ac.at<mailto:Wien@zeus.theochem.tuwien.ac.at> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html -- Kind Regards Muhammad Sajjad Post Doctoral Fellow KAUST, KSA. _______________________________________________ Wien mailing list Wien@zeus.theochem.tuwien.ac.at<mailto:Wien@zeus.theochem.tuwien.ac.at> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html -- Kind Regards Muhammad Sajjad Post Doctoral Fellow KAUST, KSA. _______________________________________________ Wien mailing list Wien@zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
