I want to check implementation of Hybrid functional in QE, to see how it works well (on Silicon). Choice of Silicon is obvious because of its extensive study. At present I did not find any method to obtain the Bandstructure using Hybrid functionals in PWSCF. A dense grid is computationally expensive and so I want to find another method to obtain the Bandstructure using Hybrid Functionals. I want to extend the method for other Gr IV materials like Ge, Sn and alloys. Let me repeat my simulation scheme, 1. Do scf calculations using GGA. 2. Do scf calculations using HSE. restart_mode='restart', modify K_POINTS using a K mesh generated using perl script given in Wannier90 3. use Wannier90 as Postprocessing tool and plot the bandstructure.
This method ends up in to lot of errors in selecting the K points and q mesh for HSE, but from my forum research, I find that this is only method available. Any comments? Please suggest if another method is possible. On Sun, May 17, 2015 at 6:41 PM, nicvok <[email protected]> wrote: > Dear Dhirendra, > > which information do you need exactly for silicon. Only the bandstructure > which is near the experiment? > Sure, due to the connection of the hamiltonian/Eigenvalues to charge > density AND wavefunctions a nscf calculation won’t do the trick, but I am > pretty sure > that a „dense“ scf-calculation with paths you need for a bandstructure > will work out. Otherwise maybe even a simple sp3s* > tight-binding calculation will be enough for your needs - it works quite > well for Si. > I have no idea, what you did with the Wannier functions - usually you need > proper Eigenvalues (in your case the HSE bandstructure) > where you map onto. Building a Wannier-based Hamiltonian from LDA/GGA > Eigenvalues won’t give a leap forward. > > bests > 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 > -------------------------------------------------------- > > Am 17.05.2015 um 12:00 schrieb [email protected]: > > Date: Sun, 17 May 2015 05:29:29 +0530 > From: DHIRENDRA VAIDYA <[email protected]> > Subject: [Pw_forum] Si Bandstructure in HSE: Wannier90 > To: PWSCF Forum <[email protected]> > Message-ID: > <CAJLtapV=mb6tdgfej9o8pkoj0fzxmo7pxjjh8auwyasz-k7...@mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > > Hi, > > So far PWSCF provides little help in Silicon bandstructure using HSE. But > from PWSCF forum it is clear to me now that in HSE nscf calculations cannot > be performed. The VASP method of zero weights on KPOINTS doesn't work due > to an error ' k+q is not an s*k'. I had some success in using Wannier90 as > post processing tool. Is it the right way to obtain the bandstructure of > Si? > > -- > -- > Dhirendra > > > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum > -- -- Dhirendra
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