Please think about the following questions: 1) Why is your number for the band gap "wrong", whereas what someone else calculated with HSE is "right"? 2) What is the purpose of optimising internal and cell parameters? 3) Are the cell and internal parameters of PBEsol the same as what they should be with mBJ? What does "should be" mean here?
_____ Professor Laurence Marks "Research is to see what everybody else has seen, and to think what nobody else has thought", Albert Szent-Gyorgi www.numis.northwestern.edu On Feb 8, 2018 3:41 AM, "Dr. K. C. Bhamu" <kcbham...@gmail.com> wrote: No, I said the calculated gal is ~0.3eV less then the reported gap: HSE. I tested this on more than 10 systems and in each case obsessed this band gap discrepancy. Regards Bhamu On Feb 8, 2018 3:05 PM, <t...@theochem.tuwien.ac.at> wrote: > A band gap of 0.3 eV is very small and a change of lattice constant may > be enough to close the band gap. > > On Thursday 2018-02-08 10:30, Dr. K. C. Bhamu wrote: > > Date: Thu, 8 Feb 2018 10:30:29 >> From: Dr. K. C. Bhamu <kcbham...@gmail.com> >> Reply-To: A Mailing list for WIEN2k users <w...@zeus.theochem.tuwien.ac. >> at> >> To: A Mailing list for WIEN2k users <Wien@zeus.theochem.tuwien.ac.at> >> Subject: Re: [Wien] a note on lattice parameter optimization >> >> Yes, I used PBESol followed by mBJ. >> >> On Feb 8, 2018 2:28 PM, <t...@theochem.tuwien.ac.at> wrote: >> Hi, >> >> Did you use mBJ to calculate the band gap in both procedures? >> >> FT >> >> On Thursday 2018-02-08 09:35, Dr. K. C. Bhamu wrote: >> >> Date: Thu, 8 Feb 2018 09:35:08 >> From: Dr. K. C. Bhamu <kcbham...@gmail.com> >> Reply-To: A Mailing list for WIEN2k users < >> wien@zeus.theochem.tuwien.ac.at> >> To: A Mailing list for WIEN2k users < >> Wien@zeus.theochem.tuwien.ac.at> >> Subject: [Wien] a note on lattice parameter optimization >> >> Hello, >> >> Using experimental lattice parameters(a Ang), I optimized the >> structure with two options. >> >> 1. Directly optimized the structure without min_lapw ... and >> the optimized lattice parameters are in the vicinity of Exp a (~0.01 Ang >> accuracy) and the calculated band gap (from mBJ2) is in agreement with >> reported value ~0.3 eV less. >> >> 2. First relaxed the structure and then optimized this relaxed >> structure (without min_lapw ....). In this case the optimized lattice >> parameters are reduced by ~0.05 Ang and the band gap vanished or largely >> reduced. >> >> >> Why is the second way of doing band structure not working? >> >> I tested it on many systems. In some case system became metal >> and in some cases band gap largely reduced when I used the fully relaxed >> structure for optimization. >> >> >> Thanks, >> >> >> Bhamu >> >> >> >> >> >> >> _______________________________________________ >> Wien mailing list >> Wien@zeus.theochem.tuwien.ac.at >> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien >> <https://urldefense.proofpoint.com/v2/url?u=http-3A__zeus.theochem.tuwien.ac.at_mailman_listinfo_wien&d=DwMFaQ&c=yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=jl0lHi-CtjMpp__lsTB6ZTdAJ0Xy47bf44CPXSBt7QE&s=xezPeLzVIzkyNQZdVyrkfiQm7d4wtaXeocIv-y-KdUY&e=> >> SEARCH the MAILING-LIST at: http://www.mail-archive.com/wi >> e...@zeus.theochem.tuwien.ac.at/index.html >> <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.mail-2Darchive.com_wien-40zeus.theochem.tuwien.ac.at_index.html&d=DwMFaQ&c=yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=jl0lHi-CtjMpp__lsTB6ZTdAJ0Xy47bf44CPXSBt7QE&s=1EhCR6okBj_tGDzqdgSAxNSZftNyujAJxvs8z3T7sq4&e=> >> >> >> > _______________________________________________ > Wien mailing list > Wien@zeus.theochem.tuwien.ac.at > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien > <https://urldefense.proofpoint.com/v2/url?u=http-3A__zeus.theochem.tuwien.ac.at_mailman_listinfo_wien&d=DwMFaQ&c=yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=jl0lHi-CtjMpp__lsTB6ZTdAJ0Xy47bf44CPXSBt7QE&s=xezPeLzVIzkyNQZdVyrkfiQm7d4wtaXeocIv-y-KdUY&e=> > SEARCH the MAILING-LIST at: http://www.mail-archive.com/wi > e...@zeus.theochem.tuwien.ac.at/index.html > <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.mail-2Darchive.com_wien-40zeus.theochem.tuwien.ac.at_index.html&d=DwMFaQ&c=yHlS04HhBraes5BQ9ueu5zKhE7rtNXt_d012z2PA6ws&r=U_T4PL6jwANfAy4rnxTj8IUxm818jnvqKFdqWLwmqg0&m=jl0lHi-CtjMpp__lsTB6ZTdAJ0Xy47bf44CPXSBt7QE&s=1EhCR6okBj_tGDzqdgSAxNSZftNyujAJxvs8z3T7sq4&e=> > >
_______________________________________________ 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
