<div dir="ltr"><div>Dear Bhamu,</div><div><br></div><div>you better use two different kinds for the Fe in octahedral sites: one for 2+ the other for 3+. they are likely to have different U's as well.</div><div><br></div><div>Matteo</div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Il giorno mer 1 dic 2021 alle ore 11:34 Dr. K. C. Bhamu <<a href="mailto:kcbhamu85@gmail.com">kcbhamu85@gmail.com</a>> ha scritto:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_default" style="font-size:large">Dear Dr. Matteo,</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">Thank you very much for the quick response.</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">Yes, I am doing vc-relax in between each step. Doing vc-relax without adopting geometry information from the previous run. I am only supplying the HP file containing U+V obtained from the previous run for the vc-relax for the next step.</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">Fe1 (octahedral coordination) atom has a mixed charge state (Fe3+ and Fe2+).</div><div class="gmail_default" style="font-size:large">The magnetic moment of Fe1( Fe3+) cancels out with Fe2 (tetrahedral coordination; all Fe3+) and the resultant magnetic moment comes from Fe1 (2+) atoms.</div><div class="gmail_default" style="font-size:large"><div class="gmail_default">According to <a href="https://www.sciencedirect.com/science/article/abs/pii/S0039602812000544" target="_blank">Ref. [1]</a>, I set all Fe1 as up and all Fe2 as down spins.</div><div class="gmail_default"><br></div><div class="gmail_default">Do you think my input still has some issues?</div><div class="gmail_default"><br></div></div><div class="gmail_default" style="font-size:large">-------------------</div><div class="gmail_default" style="font-size:large"><div class="gmail_default">I am providing some additional information here.</div><div class="gmail_default"><br></div></div><div class="gmail_default" style="font-size:large"><div class="gmail_default">Additional information:</div><div class="gmail_default"><br></div></div><div class="gmail_default" style="font-size:large"><a href="https://www.sciencedirect.com/science/article/abs/pii/S0039602812000544" target="_blank">Ref. [1]</a> </div><div class="gmail_default" style="font-size:large">Just below Fig. 3 it is mentioned that "For Fe3O4 having ferrimagnetic property, the spin of the octahedral and tetrahedral Fe was set as up and down,
respectively."</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">Relevant para from <a href="https://link.springer.com/article/10.1134%2FS1027451010030079" target="_blank">Ref. [2]</a> is as below:</div><div class="gmail_default" style="font-size:large">Fe2+ cations in the face-centered cubic lattice formed
by oxygen anions occupy octahedral sites, while Fe3+
cations are distributed between octahedral and tetrahedral sites. The trivalent Fe3+ ion is in the state with a
spin S = 5/2 and zero orbital moments. The bivalent
Fe2+ ion has a spin of 2, and its contribution comes to
~4μB unless one considers a certain possible contribution from the orbital moment [2]. The measured value of
the magnetic moment for magnetite is 4.1μB. The
magnetic moments of Fe3+ ions are antiparallel to
each other, and the observed moment is determined by
Fe2+ ions only (Fig. 1).<br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">Thanks and regards</div><div class="gmail_default" style="font-size:large">Bhamu</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large"><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Dec 1, 2021 at 2:17 PM Matteo Cococcioni <<a href="mailto:matteo.cococcioni@unipv.it" target="_blank">matteo.cococcioni@unipv.it</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div>the fourth iteration does not look too good to me as the U for Fe2 is suddenly going from 4.31 to 0.7.</div><div>Fe3O4 is a difficult system of its own. are you sure that all the Fe1 are of the same kind (3+)? The system is for sure</div><div>a mixed valence one but I don't remember how this matches its magnetic structure. Are you relaxing the structure in between?</div><div>Maybe because of the structure changes hp is not recognizing the neighbors it had before for each Fe.</div><div><br></div><div>Regards,</div><div><br></div><div>Matteo<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Il giorno mer 1 dic 2021 alle ore 06:07 Dr. K. C. Bhamu <<a href="mailto:kcbhamu85@gmail.com" target="_blank">kcbhamu85@gmail.com</a>> ha scritto:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_default" style="font-size:large">Dear Iurii,</div><div class="gmail_default" style="font-size:large">This is from the calculation without nbnd in QE input file (QE input and HP input are supplied at the end of this email).</div><div class="gmail_default" style="font-size:large">I am trying to get a converged value of U+V. Up to four steps, all the calculations seem to be fine (other than the converged value of U+V). But in the 5th step, I see that my calculations are not converging.</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">I am getting this message:</div><div class="gmail_default" style="font-size:large"> atom # 5 q point # 3 iter # 180<br> chi: 1 -83.8242814567 residue: 103.6191835332<br> chi: 2 -83.8242814548 residue: 103.6191835384<br> chi: 3 ************** residue: 381.0626501229<br> chi: 4 ************** residue: 326.7198566114<br> chi: 5 317.5473216386 residue: 329.6382092529<br> chi: 6 ************** residue: 580.5784405595<br> chi: 7 9.0496504843 residue: 1.9763844786<br> chi: 8 -6.2884312048 residue: 21.8495062869<br> chi: 9 9.0496505082 residue: 1.9763845088<br> chi: 10 -6.2884312084 residue: 21.8495062832<br> chi: 11 10.2338160751 residue: 7.3557134894<br> chi: 12 -5.1687829951 residue: 22.9825921172<br> chi: 13 6.7503553298 residue: 7.1360232476<br> chi: 14 -3.9982889995 residue: 27.0388948104<br> Average number of iter. to solve lin. system: 23.6<br> Total CPU time : 63284.6 s<br></div><div class="gmail_default" style="font-size:large">###################</div><div class="gmail_default" style="font-size:large"> atom # 5 q point # 3 iter # 274<br> chi: 1 ************** residue: **************<br> chi: 2 ************** residue: **************<br> chi: 3 ************** residue: **************<br> chi: 4 ************** residue: **************<br> chi: 5 ************** residue: **************<br> chi: 6 ************** residue: **************<br> chi: 7 ************** residue: 78.8265104616<br> chi: 8 190.5140692168 residue: **************<br> chi: 9 ************** residue: 78.8264974402<br> chi: 10 190.5140679621 residue: **************<br> chi: 11 ************** residue: **************<br> chi: 12 544.1915326984 residue: **************<br> chi: 13 ************** residue: **************<br> chi: 14 ************** residue: **************<br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">U+V value from four completed calculations is given below:</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">site n. type label spin new_type new_label Hubbard U (eV)<br> 1 1 Fe1 1 1 Fe1 5.1791<br> 5 2 Fe2 -1 2 Fe2 5.0962<br> 7 3 O 0 3 O 7.1203<br><br>site n. type label spin new_type new_label Hubbard U (eV)<br> 1 1 Fe1 1 1 Fe1 5.6013<br> 5 2 Fe2 -1 2 Fe2 4.3164<br> 7 3 O 0 3 O 7.5401<br><br>site n. type label spin new_type new_label Hubbard U (eV)<br> 1 1 Fe1 1 1 Fe1 5.6013<br> 5 2 Fe2 -1 2 Fe2 4.3164<br> 7 3 O 0 3 O 7.5401<br><br>site n. type label spin new_type new_label Hubbard U (eV)<br> 1 1 Fe1 1 1 Fe1 4.4843<br> 5 2 Fe2 -1 2 Fe2 0.7259<br> 7 3 O 0 3 O 7.3480<br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">I do not think changing "conv_thr_chi" will help here as the number is still oscillating in integer values.</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">What suggestions do you have for this situation?</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large">HP input file:</div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large"> &inputhp<br> prefix = 'pwscf',<br>niter_max=300<br> outdir = './temp/',<br> nq1 = 2, nq2 = 2, nq3 = 2,<br> conv_thr_chi = 1.0d-5,<br>find_atpert = 1<br>docc_thr=1.d-3<br>!disable_type_analysis=.true.,<br>/<br></div><div class="gmail_default" style="font-size:large"><br></div><div class="gmail_default" style="font-size:large"><div class="gmail_default">QE input file:</div><div class="gmail_default">&CONTROL<br> calculation = 'vc-relax'<br> restart_mode='from_scratch',<br> etot_conv_thr = 1.4000000000d-04<br> forc_conv_thr = 1.0000000000d-04<br> outdir = './temp/'<br> prefix = 'pwscf'<br> pseudo_dir = '~/PPs/jana_2/'<br> tprnfor = .true.<br> tstress = .true.<br> verbosity = 'high'<br>/<br>&SYSTEM<br> degauss = 0.022<br> ecutrho = 320<br> ecutwfc = 40<br> occupations = 'smearing' , smearing = 'mp'<br> ibrav = 0<br> nat = 14<br> nosym = .false.<br> ntyp = 3<br>nspin=2<br> starting_magnetization(1) = 0.8<br> starting_magnetization(2) = -0.8<br> starting_magnetization(3) = 0.0<br><br> lda_plus_u = .true.,<br> lda_plus_u_kind = 2,<br> U_projection_type = 'ortho-atomic',<br> !Hubbard_V(1,1,1) = 1.d-8<br> !Hubbard_V(5,5,1) = 1.d-8<br> !Hubbard_V(7,7,1) = 1.d-8<br>Hubbard_parameters = 'file'<br><br><br>/<br>&ELECTRONS<br> conv_thr = 1.0000000000d-06<br> electron_maxstep = 400<br> mixing_beta = 1.5000000000d-01<br>/<br>&IONS<br> ion_dynamics = 'bfgs'<br> /<br>&CELL<br>/<br><br>ATOMIC_SPECIES<br>Fe1 55.845 Fe.pbe-nd-rrkjus.UPF<br>Fe2 55.845 Fe.pbe-nd-rrkjus.UPF<br>O 15.9994 O.pbe-rrkjus.UPF<br>ATOMIC_POSITIONS (crystal)<br>Fe1 0.0000000000 -0.0000000000 -0.0000000000<br>Fe1 0.5000000000 0.0000000000 0.0000000000<br>Fe1 0.9999999892 0.5000000216 -0.0000000000<br>Fe1 0.9999999965 0.9999999956 0.5000000115<br>Fe2 0.3749993721 0.3749993349 0.3750019210<br>Fe2 0.6250006225 0.6250006532 0.6249981020<br>O 0.2454868415 0.2454868399 0.2454949640<br>O 0.7545131845 0.7545131098 0.7545050345<br>O 0.7635313546 0.2454868399 0.2454949640<br>O 0.2364686713 0.7545131098 0.7545050345<br>O 0.2454868307 0.7635313746 0.2454949640<br>O 0.7545132523 0.2364686217 0.7545050345<br>O 0.2454908593 0.2454908222 0.7635274591<br>O 0.7545090629 0.7545091741 0.2364725394<br><br>CELL_PARAMETERS (angstrom)<br> 5.944682649 0.000000000 0.000000000<br> 2.972341325 5.148246192 0.000000000<br> 2.972341325 1.716082064 4.853885701<br><br>K_POINTS automatic<br>7 7 7 0 0 0<br></div><div class="gmail_default"><br></div><div class="gmail_default"><br></div><div class="gmail_default">Regards</div><div class="gmail_default">Bhamu</div></div><div class="gmail_default" style="font-size:large"><br></div></div>
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Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu" rel="noreferrer" target="_blank">www.max-centre.eu</a>)<br>
users mailing list <a href="mailto:users@lists.quantum-espresso.org" target="_blank">users@lists.quantum-espresso.org</a><br>
<a href="https://lists.quantum-espresso.org/mailman/listinfo/users" rel="noreferrer" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/users</a></blockquote></div><br clear="all"><br>-- <br><div dir="ltr"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>Matteo Cococcioni<br></div><div>Department of Physics<br></div>University of Pavia<br>Via Bassi 6, I-27100 Pavia, Italy<br>tel +39-0382-987485<br><div>e-mail <a href="mailto:lucio.andreani@unipv.it" target="_blank">matteo.cococcioni@unipv.it</a></div></div></div></div></div></div></div>
_______________________________________________<br>
Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu" rel="noreferrer" target="_blank">www.max-centre.eu</a>)<br>
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_______________________________________________<br>
Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu" rel="noreferrer" target="_blank">www.max-centre.eu</a>)<br>
users mailing list <a href="mailto:users@lists.quantum-espresso.org" target="_blank">users@lists.quantum-espresso.org</a><br>
<a href="https://lists.quantum-espresso.org/mailman/listinfo/users" rel="noreferrer" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/users</a></blockquote></div><br clear="all"><br>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>Matteo Cococcioni<br></div><div>Department of Physics<br></div>University of Pavia<br>Via Bassi 6, I-27100 Pavia, Italy<br>tel +39-0382-987485<br><div>e-mail <a href="mailto:lucio.andreani@unipv.it" target="_blank">matteo.cococcioni@unipv.it</a></div></div></div></div></div></div></div>