Dear Merlin,
By the way, since you are using DFPT+U to compute phonons including the Hubbard U correction, I would like to let you (and others) know that the paper describing DFPT+U has been just published in Physical Review B: A. Floris, I. Timrov, B. Himmetoglu, N. Marzari, S. de Gironcoli, and M. Cococcioni, "Hubbard-corrected density functional perturbation theory with ultrasoft pseudopotentials", Phys. Rev. B 101, 064305 (2020). Best 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 Timrov Iurii <[email protected]> Sent: Wednesday, February 19, 2020 10:05:01 AM To: Quantum ESPRESSO users Forum Subject: Re: [QE-users] non-convergency of DFPT+U calculation Dear Merlin, Total magnetization must be zero for an antiferromagnetic insulator. Hence, some deviation from zero that you obtain is probably a numerical noise (I would check the convergence of the results: reduce conv_thr, increase the size of the k mesh, etc., and relax well the structure). > If I wanted to be closer to the smearing calculation, I would have to > consider nocolin=.true., is that right? DFPT+U with noncolin=.true. is not implemented. Greetings, 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 Merlin Meheut <[email protected]> Sent: Wednesday, February 19, 2020 12:38:08 AM To: Quantum ESPRESSO users Forum Subject: Re: [QE-users] non-convergency of DFPT+U calculation Dear Iurii, Thank you again for your help! So far, the Example02 seems quite clear to me, although it will take me some time to apply it to my system and check that everything is working. One quick question, though: in my case, the "total magnetization" obtained from the first calculation (with smearing) is non-zero and non-integer: "total magnetization = -0.63 Bohr mag/cell" (which makes sense since I have two different sites). As I understand it, for the second calculation, the variable tot_magnetization should be integer, so I can only take it equal to 0 or 1 here (I tried with 0, I don't know which is better). If I wanted to be closer to the smearing calculation, I would have to consider nocolin=.true., is that right? Greetings, Merlin Le mar. 18 févr. 2020 à 17:32, Timrov Iurii <[email protected]<mailto:[email protected]>> a écrit : Dear Merlin, > Does that mean that magnetic insulators cannot be treated by Quantum Espresso? It is possible to model magnetic insulators in Quantum ESPRESSO. I am using the procedure described in q-e-qe-6.5/HP/examples/example02/README. If the description in README file is not clear enough, please let me know. Greetings, 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]<mailto:[email protected]>> on behalf of Merlin Meheut <[email protected]<mailto:[email protected]>> Sent: Tuesday, February 18, 2020 5:21:46 PM To: Quantum ESPRESSO users Forum Subject: Re: [QE-users] non-convergency of DFPT+U calculation Hi Iurii, First thank you very much for this remark, I did not know that one could not use tot_magnetization and starting_magnetization together. Indeed, this is reported in the Documentation INPUT_PW.def. At this point, however, I don't see how to make an input for an antiferromagnetic insulating material (which is the goal here). Because with this input, the state is non magnetic: &system ibrav =8, celldm(1)=9.107535, celldm(2)=2.17425, celldm(3)=1.263056, nat =28, ntyp = 4, ecutwfc =80.0, ecutrho = 320.0, nspin=2, tot_magnetization=0, lda_plus_u = .true., U_projection_type = 'atomic', Hubbard_U(1)=2.4, Hubbard_U(2)=2.6, ! valeurs Yu et al 2013 =2.4/2.6 /&end And if you use this input: &system ibrav =8, celldm(1)=9.107535, celldm(2)=2.17425, celldm(3)=1.263056, nat =28, ntyp = 4, ecutwfc =${a}.0, ecutrho = ${b}.0, nspin=2, starting_magnetization(1)=0.5, starting_magnetization(2)=-0.5, lda_plus_u = .true., U_projection_type = 'atomic', Hubbard_U(1)=2.5, Hubbard_U(2)=2.5, /&end ,you have an error message: %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Error in routine iosys (1): fixed occupations and lsda need tot_magnetization %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% So as you say, using starting_magnetization imposes using smearing. But if I am correct, smearing means that your material is metallic, and therefore you cannot compute dielectric quantities or effective charges with phonon. Actually, in the INPUT_PW.def file, the word "antiferromagnetic" is only present once, in the "starting_magnetization" definitions. Does that mean that magnetic insulators cannot be treated by Quantum Espresso? Would you have any hint as to how to extract myself from such a dead end? Thanks again for your help, Greetings, Merlin Le dim. 16 févr. 2020 à 23:11, Timrov Iurii <[email protected]<mailto:[email protected]>> a écrit : Dear Merlin, In your input for the PW calculation you have: > tot_magnetization=0, > starting_magnetization(1)=0.5, starting_magnetization(2)=-0.5 tot_magnetization and starting_magnetization must not be used together (please check the documentation). Moreover, starting_magnetization must be used with occupations='smearing', but I do not see smearing in your input. Is the ground state metallic or insulating? How many representations do you have in total? And only #23 diverges? Not sure this will help, but you may try to use dual = ecutrho/ecutwfc = 12, with ecutwfc=80 Ry. > Si 27.9769 Si.pz2.UPF > O 15.9949 O.pz.UPF I do not know what are these pseudos, and how good/bad are they. You can try to check the SSSP library. > Fe1 55.9349 Fe.pz-n-rrkjus_psl.1.0.0.UPF > Fe2 55.9349 Fe.pz-n-rrkjus_psl.1.0.0.UPF Also for these I would check the SSSP library. Greetings, 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]<mailto:[email protected]>> on behalf of Merlin Meheut <[email protected]<mailto:[email protected]>> Sent: Sunday, February 16, 2020 9:22:57 PM To: Quantum Espresso users Forum Subject: [QE-users] non-convergency of DFPT+U calculation Dear PWSCF users, I am trying to realize a phonon calculation (at gamma) with +U on fayalite (olivine structure Fe2SiO4) with anti-ferromagnetic configuration , and whether the calculation goes fine without +U, I have one representation (#23) that systematically fails to converge when I add a +U. I tried several values for the +U (0.5, 2.5, 4), several functionals (PZ, PBE), but the result is always the same. I have used QE versions 6.4 and 6.4.1 on two different computing centers . Would you have any idea about the reasons for such a failure? I am specifically worried by one output message: "Atomic wfc used for the DFT+U projector are NOT orthogonalized", but I don't know how to fix that. Here are examples of my scf and ph inputs, and the failing ph output: scf: &control calculation = 'scf', (...) tprnfor = .true., tstress = .true., /&end &system ibrav =0, celldm(1)=9.107535, nat =28, ntyp = 4, ecutwfc =80.0, ecutrho = 320.0, nspin=2, tot_magnetization=0, starting_magnetization(1)=0.5, starting_magnetization(2)=-0.5, lda_plus_u = .true., U_projection_type = 'atomic', Hubbard_U(1)=2.4, Hubbard_U(2)=2.6 /&end &electrons electron_maxstep = 150, conv_thr = 1.d-11, mixing_mode = 'plain', startingwfc = 'atomic', mixing_beta = 0.3, /&end ATOMIC_SPECIES Fe1 55.9349 Fe.pz-n-rrkjus_psl.1.0.0.UPF Fe2 55.9349 Fe.pz-n-rrkjus_psl.1.0.0.UPF Si 27.9769 Si.pz2.UPF O 15.9949 O.pz.UPF (...) ph input: &inputph amass(1)=55.9349, amass(2)=55.9349, amass(3)=27.9769, amass(4)=15.9949, alpha_mix(1) = 0.5, ! ldisp=.true., nq1=2, nq2=2, nq3=2, tr2_ph = 1.0D-17, prefix='FAYA2', fildyn='mat.$PREFIX', lraman=.false., epsil =.false., trans =.true., zue = .false., zeu= .false., start_irr=23, last_irr=23, outdir ='./', /&end 0.0 0.0 0.0 ph output: Representation # 23 mode # 23 Self-consistent Calculation iter # 1 total cpu time : 58.7 secs av.it<http://av.it>.: 8.5 thresh= 1.000E-02 alpha_mix = 0.500 |ddv_scf|^2 = 1.045E-06 iter # 2 total cpu time : 62.9 secs av.it<http://av.it>.: 23.0 thresh= 1.022E-04 alpha_mix = 0.500 |ddv_scf|^2 = 2.668E-04 iter # 3 total cpu time : 66.4 secs av.it<http://av.it>.: 17.5 thresh= 1.633E-03 alpha_mix = 0.500 |ddv_scf|^2 = 3.033E-03 iter # 4 total cpu time : 69.0 secs av.it<http://av.it>.: 11.0 thresh= 5.508E-03 alpha_mix = 0.500 |ddv_scf|^2 = 5.602E-02 iter # 5 total cpu time : 73.0 secs av.it<http://av.it>.: 15.5 thresh= 1.000E-02 alpha_mix = 0.500 |ddv_scf|^2 = 1.238E+00 iter # 6 total cpu time : 76.7 secs av.it<http://av.it>.: 19.5 thresh= 1.000E-02 alpha_mix = 0.500 |ddv_scf|^2 = 2.841E+01 iter # 7 total cpu time : 80.9 secs av.it<http://av.it>.: 23.0 thresh= 1.000E-02 alpha_mix = 0.500 |ddv_scf|^2 = 6.534E+02 iter # 8 total cpu time : 85.3 secs av.it<http://av.it>.: 24.5 thresh= 1.000E-02 alpha_mix = 0.500 |ddv_scf|^2 = 1.446E+04 iter # 9 total cpu time : 90.1 secs av.it<http://av.it>.: 27.5 thresh= 1.000E-02 alpha_mix = 0.500 |ddv_scf|^2 = 3.214E+05 iter # 10 total cpu time : 95.5 secs av.it<http://av.it>.: 30.0 thresh= 1.000E-02 alpha_mix = 0.500 |ddv_scf|^2 = 7.200E+06 (.....) Thank you in advance for your help! Feel free to ask for any further calculation details. Regards, -- Merlin Méheut adresse labo: GET - OMP - Université Paul Sabatier 14 avenue Edouard Belin 31400 Toulouse FRANCE tel: (+33) 5 61 33 26 17 _______________________________________________ Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso<http://www.max-centre.eu/quantum-espresso>) users mailing list [email protected]<mailto:[email protected]> https://lists.quantum-espresso.org/mailman/listinfo/users -- Merlin Méheut adresse labo: GET - OMP - Université Paul Sabatier 14 avenue Edouard Belin 31400 Toulouse FRANCE tel: (+33) 5 61 33 26 17 _______________________________________________ Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso<http://www.max-centre.eu/quantum-espresso>) users mailing list [email protected]<mailto:[email protected]> https://lists.quantum-espresso.org/mailman/listinfo/users -- Merlin Méheut adresse labo: GET - OMP - Université Paul Sabatier 14 avenue Edouard Belin 31400 Toulouse FRANCE tel: (+33) 5 61 33 26 17
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