Dear Prasad, there are not sufficient data to understand what's happening. 1) DFT systematically underestimates band gaps, to what extent depends on the material. If this is the case there is nothing to do unless moving to other approximations that at least partially solve this problem (DFT+U,hybrid functionals,GW,....) 2) do the references you mention concern theoretical estimations within DFT or experimental data? While when comparing with experiments you might experient the limit of the previous point, whereas if you find other calculations, within the same level of approximation, you should find at least similar (if not equal) results 3) in the case you have reference calculations to compare with and there is no agreement, check your input geometry and unit cell (to understand if they are wrong) as well as the convergence parameters (Brillouin zone sampling, wave function cutoff, charge density cutoff if it applies, ....)
Giovanni -- Giovanni Cantele, PhD CNR-SPIN c/o Dipartimento di Fisica Universita' di Napoli "Federico II" Complesso Universitario M. S. Angelo - Ed. 6 Via Cintia, I-80126, Napoli, Italy e-mail: [email protected] <[email protected]> Phone: +39 081 676910 Skype contact: giocan74 ResearcherID: http://www.researcherid.com/rid/A-1951-2009 Web page: https://sites.google.com/view/giovanni-cantele/home Il giorno ven 16 feb 2024 alle ore 10:40 PRASAD SANKALPA WANNINAYAKA < [email protected]> ha scritto: > Dear QE users, > I am studying the electronic properties of FeTiO3 using QE when > calculating the band structure using 'bands.x' calculation. I obtained the > bandgap as 0.01eV but according to references that value is 2.54 eV. i need > to know why this is happening. > > Thank you > Best regards > Prasad Sankalpa > Physics Undergraduate > > ------------------------------ > > The information of this email is confidential. If you have received it by > error, please inform us by email and then delete the message. It is illegal > to disclose the contents of this message to anyone. The integrity or > security of this email cannot be guaranteed over the Internet. Therefore, > the sender/university will not be responsible for any damage caused by this > email. > > SINHALA <https://cmb.ac.lk/email-policy/sinhala#disclaimer> | TAMIL > <https://cmb.ac.lk/email-policy/tamil#disclaimer> > _______________________________________________ > The Quantum ESPRESSO community stands by the Ukrainian > people and expresses its concerns about the devastating > effects that the Russian military offensive has on their > country and on the free and peaceful scientific, cultural, > and economic cooperation amongst peoples > _______________________________________________ > Quantum ESPRESSO is supported by MaX (www.max-centre.eu) > users mailing list [email protected] > https://lists.quantum-espresso.org/mailman/listinfo/users
_______________________________________________ The Quantum ESPRESSO community stands by the Ukrainian people and expresses its concerns about the devastating effects that the Russian military offensive has on their country and on the free and peaceful scientific, cultural, and economic cooperation amongst peoples _______________________________________________ Quantum ESPRESSO is supported by MaX (www.max-centre.eu) users mailing list [email protected] https://lists.quantum-espresso.org/mailman/listinfo/users
