Dear Iurii, Many thanks. It seems that turbo_eels does not work with nspin = 2. It gives an error:
Error in routine lr_readin (1): LSDA is not implemented But it does work without npsin = 2 but with smearing and tot_charge = 0/-1/+1 Best, Abhirup ------------------------------------------------------------------------------------------------------------------------------------- Abhirup Patra Postdoctoral Research Fellow Department of Chemistry University of Pennsylvania On Thu, Dec 19, 2019 at 11:49 AM Timrov Iurii <[email protected]> wrote: > Dear Abhirup, > > > Thank you for clarifications! > > > Please note that the turbo_eels code works for the noncollinear > spin-polarization (noncolin=.true.), and including the spin-orbit coupling > (if needed). The turbo_eels code works for the general k-points > implementation (k=0 is allowed), but it does not work for the "gamma_only" > case (i.e. using tricks to speed up calculations). > > > The turbo_lanczos and turbo_davidson codes (which are for the absorption > spectroscopy) do not work in the spin-polarized case (both collinear and > noncollinear) - yes, you are right. > > > Best, > > Iurii > > > -- > Dr. Iurii Timrov > Postdoctoral Researcher > STI - IMX - THEOS and NCCR - MARVEL > Swiss Federal Institute of Technology Lausanne (EPFL) > CH-1015 Lausanne, Switzerland > +41 21 69 34 881 > http://people.epfl.ch/265334 > ------------------------------ > *From:* users <[email protected]> on behalf of > Abhirup Patra <[email protected]> > *Sent:* Thursday, December 19, 2019 5:40:47 PM > *To:* Quantum ESPRESSO users Forum > *Subject:* Re: [QE-users] k-point algorithm is not tested yet turbo > davidson > > Dear Iurii, > > Thanks for the email. Sorry about not explaining it well. Here is what I > meant: With spin-polarization and with gamma only kmesh none of the TDDFT > code works (i.e. turbo_davidson, turbo_eels, turbo_lanczos). So it is > difficult to simulate optical spectra for a "neutral (tot_charge = 0)" > doped/defected structure. By "works", I meant that I could run the regular > scf-calculation and TDDFT codes for any "non-zero (tot_charge = -1 or +1)" > charged structure using "gamma only" kmesh and "non spin-polarization". > > Please let me know if it's still confusing. > > Best, > Abhirup > > > > ------------------------------------------------------------------------------------------------------------------------------------- > Abhirup Patra > Postdoctoral Research Fellow > Department of Chemistry > University of Pennsylvania > > > On Thu, Dec 19, 2019 at 4:06 AM Timrov Iurii <[email protected]> wrote: > >> Dear Abhirup, >> >> >> Sorry, I miss the point. Could you clarify please what do you mean by >> saying "it works"? Do you refer to the k-points implementation of the >> turbo_davidson code or something else? The k-points algorithm must be >> disabled for all cases (neutral and charged cases), and if this not the >> case, then I will modify the code in order to disable it. >> >> >> Best, >> >> Iurii >> >> >> -- >> Dr. Iurii Timrov >> Postdoctoral Researcher >> STI - IMX - THEOS and NCCR - MARVEL >> Swiss Federal Institute of Technology Lausanne (EPFL) >> CH-1015 Lausanne, Switzerland >> +41 21 69 34 881 >> http://people.epfl.ch/265334 >> ------------------------------ >> *From:* users <[email protected]> on behalf of >> Abhirup Patra <[email protected]> >> *Sent:* Wednesday, December 18, 2019 9:36:51 PM >> *To:* Quantum ESPRESSO users Forum >> *Subject:* Re: [QE-users] k-point algorithm is not tested yet turbo >> davidson >> >> Forgot to mention, it only happens if I do not assign any charge to the >> structure i.e., for neutral case. However, it works for nonzero tot_charge, >> spin-unpolarized situation with fixed smearing and turb_davidson works fine. >> >> Thanks for your comments. >> >> Best, >> Abhirup >> >> ------------------------------------------------------------------------------------------------------------------------------------- >> Abhirup Patra >> Postdoctoral Research Fellow >> Department of Chemistry >> University of Pennsylvania >> >> >> On Wed, Dec 18, 2019 at 3:29 PM Abhirup Patra <[email protected]> >> wrote: >> >>> Thanks, Iurii. Yes, the spectrum with gamma point is quite reasonable >>> but do not match with the experimental observation. It could be some other >>> issue. >>> >>> However, I am wondering how to do the TDDFT calculation for a >>> doped/defected structure with extra electron or hole. I tried to use >>> turbo_davidson starting from i) scf calculation with npsin= 2 and total >>> magnetization and turbo_davidson does not work since I believe it does not >>> for spin-polarized system, then, I tried ii) scf calculation without any >>> spin-polarization and the scf calculation did not run since it cannot work >>> with an extra charge and 'fixed' occupation, and, finally, iii) scf with >>> smearing but turbo_davidson does not support scf calculation with smearing >>> (ref: >>> https://lists.quantum-espresso.org/pipermail/users/2017-January/037363.html) >>> >>> >>> I believe in this case I cannot use TDDFT of QE to calculate absorption >>> spectra of a defected or doped structure. Am I right here? >>> >>> Best, >>> Abhirup >>> >>> >>> >>> ------------------------------------------------------------------------------------------------------------------------------------- >>> Abhirup Patra >>> Postdoctoral Research Fellow >>> Department of Chemistry >>> University of Pennsylvania >>> >>> >>> On Wed, Dec 18, 2019 at 4:00 AM Timrov Iurii <[email protected]> >>> wrote: >>> >>>> Dear Abhirup, >>>> >>>> >>>> > However, I am not sure with the number of atoms (~120 or more) GW-BSE >>>> calculations with supercell is actually feasible. >>>> >>>> >>>> Yes, I understand the issue. I do not know if it is feasible. You may >>>> try to use e.g. Yambo and see how it goes. Otherwise, since you have >>>> already quite a big cell, maybe with k=0 you obtain quite a reasonably >>>> converged spectrum (to be checked w.r.t. the cell size) at the TDDFT level >>>> in the adiabatic approximation. >>>> >>>> >>>> Regards, >>>> >>>> Iurii >>>> >>>> >>>> -- >>>> Dr. Iurii Timrov >>>> Postdoctoral Researcher >>>> STI - IMX - THEOS and NCCR - MARVEL >>>> Swiss Federal Institute of Technology Lausanne (EPFL) >>>> CH-1015 Lausanne, Switzerland >>>> +41 21 69 34 881 >>>> http://people.epfl.ch/265334 >>>> ------------------------------ >>>> *From:* users <[email protected]> on behalf of >>>> Abhirup Patra <[email protected]> >>>> *Sent:* Tuesday, December 17, 2019 4:47:01 PM >>>> *To:* Quantum ESPRESSO users Forum >>>> *Subject:* Re: [QE-users] k-point algorithm is not tested yet turbo >>>> davidson >>>> >>>> Thanks very much, Iurii. I really appreciate your answer and it does >>>> make sense to me. With gamma point only it works fine. And, you are right, >>>> my system is a solid and I am >>>> trying to simulate the optical spectrum. However, I am not sure with >>>> the number of atoms (~120 or more) GW-BSE calculations with supercell is >>>> actually feasible. >>>> >>>> Best, >>>> Abhirup >>>> >>>> ------------------------------------------------------------------------------------------------------------------------------------- >>>> Abhirup Patra >>>> Postdoctoral Research Fellow >>>> Department of Chemistry >>>> University of Pennsylvania >>>> >>>> >>>> On Tue, Dec 17, 2019 at 7:50 AM Timrov Iurii <[email protected]> >>>> wrote: >>>> >>>>> Dear Abhirup, >>>>> >>>>> >>>>> As you can see from the error message of the turbo_davidson code, the >>>>> k-points algorithm is not supported. Only Gamma point sampling can be >>>>> used. >>>>> >>>>> >>>>> If I understand correctly, your system is a solid, right? And you want >>>>> to use a unit cell with a k-points mesh, right? The turbo_davidson cannot >>>>> be used in this case. You may try to use a supercell with a Gamma point >>>>> sampling. But be careful when using TDDFT in the adiabatic approximation >>>>> for the absorption spectroscopy of solids. I recommend that you check >>>>> literature on this topic. Maybe you will need to resort to the BSE >>>>> approach. >>>>> >>>>> >>>>> HTH >>>>> >>>>> >>>>> Iurii Timrov >>>>> >>>>> >>>>> -- >>>>> Dr. Iurii Timrov >>>>> Postdoctoral Researcher >>>>> STI - IMX - THEOS and NCCR - MARVEL >>>>> Swiss Federal Institute of Technology Lausanne (EPFL) >>>>> CH-1015 Lausanne, Switzerland >>>>> +41 21 69 34 881 >>>>> http://people.epfl.ch/265334 >>>>> ------------------------------ >>>>> *From:* users <[email protected]> on behalf of >>>>> Abhirup Patra <[email protected]> >>>>> *Sent:* Monday, December 16, 2019 6:12:08 PM >>>>> *To:* Quantum ESPRESSO users Forum >>>>> *Subject:* [QE-users] k-point algorithm is not tested yet turbo >>>>> davidson >>>>> >>>>> Hello, >>>>> >>>>> I am trying to use turbo_davidson starting from a SCF calculation >>>>> using PBE without smearing and spin-polarization. This system is a >>>>> non-metal with bandgap of 2.6 eV. I gave uniform k-mesh as follows for the >>>>> bcc structure with lattice constant of 10.34 angstrom. >>>>> >>>>> K_POINTS {crystal_b} >>>>> 9 >>>>> 0.0 0.0 0.0 0 >>>>> 0.0 -0.5 0.0 0 >>>>> 0.0 -0.5 0.5 0 >>>>> 0.5 -0.5 0.5 0 >>>>> 0.5 -0.5 0.0 0 >>>>> 0.5 0.0 0.0 0 >>>>> 0.0 0.0 0.0 0 >>>>> 0.0 0.0 0.5 0 >>>>> 0.5 0.0 0.5 0 >>>>> >>>>> &lr_input >>>>> prefix = 'pristine_pbe' >>>>> outdir = './' >>>>> ! wfcdir = './' >>>>> / >>>>> &lr_dav >>>>> num_eign = 35, >>>>> num_init = 70, >>>>> num_basis_max = 200, >>>>> start = 0.0d0 >>>>> finish = 3.5d0 >>>>> step = 0.001d0 >>>>> broadening = 0.005d0 >>>>> / >>>>> >>>>> However, I am getting the following error: >>>>> >>>>> Error in routine lr_readin (1): >>>>> k-point algorithm is not tested yet >>>>> >>>>> I am wondering if there is a simple way out to this problem other than >>>>> explicitly testing different k mesh combinations. >>>>> >>>>> Best, >>>>> Abhirup >>>>> >>>>> ------------------------------------------------------------------------------------------------------------------------------------- >>>>> Abhirup Patra >>>>> Postdoctoral Research Fellow >>>>> Department of Chemistry >>>>> University of Pennsylvania >>>>> _______________________________________________ >>>>> Quantum ESPRESSO is supported by MaX ( >>>>> www.max-centre.eu/quantum-espresso) >>>>> users mailing list [email protected] >>>>> https://lists.quantum-espresso.org/mailman/listinfo/users >>>> >>>> _______________________________________________ >>>> Quantum ESPRESSO is supported by MaX ( >>>> www.max-centre.eu/quantum-espresso) >>>> users mailing list [email protected] >>>> https://lists.quantum-espresso.org/mailman/listinfo/users >>> >>> _______________________________________________ >> Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso) >> users mailing list [email protected] >> https://lists.quantum-espresso.org/mailman/listinfo/users > > _______________________________________________ > Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso) > users mailing list [email protected] > https://lists.quantum-espresso.org/mailman/listinfo/users
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