[QE-users] Need some comments on my U+V values obtained using self-consistently

Iurii TIMROV iurii.timrov at epfl.ch
Wed Nov 24 11:41:06 CET 2021


Dear Bhamu,


Just for reference, the protocol/workflow for a self-consistent calculation of Hubbard parameters is shown in Fig. 1 of Phys. Rev. B103, 045141 (2021).


> I performed only relaxed calculations in each step without updating the ionic positions for the next step.


calculation = 'relax' means that you optimize atomic positions while the lattice parameters are not changed. In our protocol in Fig. 1 by "structural optimization" we mean actually vc-relax, i.e. we optimize both the atomic positions AND lattice parameters.


> Do you think, I have followed a correct approach to get the converged U+V value?


It seems yes accept for the fact that you did 'relax' instead of 'vc-relax'.


> Do you think, the value I obtained for U+V is a converged value?


It depends what accuracy for Hubbard parameters you need. In your case you have 5.0651-5.0513=0.0138, which means that your U values are converged with the accuracy of ~0.01 eV which is more than enough for the majority of applications. But I recommend to perform 'vc-relax' between HP calculations.

HTH


Iurii


--
Dr. Iurii TIMROV
Senior Research Scientist
Theory and Simulation of Materials (THEOS)
Swiss Federal Institute of Technology Lausanne (EPFL)
CH-1015 Lausanne, Switzerland
+41 21 69 34 881
http://people.epfl.ch/265334
________________________________
From: users <users-bounces at lists.quantum-espresso.org> on behalf of Dr. K. C. Bhamu <kcbhamu85 at gmail.com>
Sent: Wednesday, November 24, 2021 10:06:49 AM
To: Quantum ESPRESSO users Forum
Subject: Re: [QE-users] Need some comments on my U+V values obtained using self-consistently

Hii Niharika,
I did not do vc-relax in between all steps except.
I performed only relaxed calculations in each step without updating the ionic positions for the next step.

Here is my script, I used for the automation:

DIR1=dir1
DIR2=dir2
DIR3=dir3
srun /home/kcbhamu/soft/qe67_kg/bin/pw.x   < FO.scf.in<http://FO.scf.in> > FO.scf.out
srun /home/kcbhamu/soft/qe67_kg/bin/hp.x   < FO.hp.in<http://FO.hp.in> > FO.hp.out


mkdir $DIR1
mv *Hubbard_parameters.dat $DIR1
mv parameters.out $DIR1
cp $DIR1/parameters.out parameters.in<http://parameters.in>
mv *out $DIR1
rm -rf temp/

sed -i 's/Hubbard_V/!Hubbard_V/g' FO.scf.in<http://FO.scf.in>
sed -i 's/!Hubbard_parameters/Hubbard_parameters/g' FO.scf.in<http://FO.scf.in>

srun /home/kcbhamu/soft/qe67_kg/bin/pw.x   < FO.scf.in<http://FO.scf.in> > FO.scf.out
srun /home/kcbhamu/soft/qe67_kg/bin/hp.x   < FO.hp.in<http://FO.hp.in> > FO.hp.out

mkdir $DIR2
mv *Hubbard_parameters.dat $DIR2
mv parameters.out $DIR2
cp $DIR2/parameters.out parameters.in<http://parameters.in>
mv *out $DIR2
rm -rf temp/

srun /home/kcbhamu/soft/qe67_kg/bin/pw.x   < FO.scf.in<http://FO.scf.in> > FO.scf.out
srun /home/kcbhamu/soft/qe67_kg/bin/hp.x   < FO.hp.in<http://FO.hp.in> > FO.hp.out

mkdir $DIR3
cp *Hubbard_parameters.dat $DIR3
cp parameters.out $DIR3
cp $DIR3/parameters.out parameters.in<http://parameters.in>
cp *out $DIR3
rm -rf temp/

Regards
Bhamu


On Wed, Nov 24, 2021 at 2:23 PM Niharika Joshi via users <users at lists.quantum-espresso.org<mailto:users at lists.quantum-espresso.org>> wrote:
Dear Bhamu sir,
I have never done convergence for U+V.
However I have done convergence of U and I did it in the similar fashion as you have described.
Only one check...when you said that you did a fresh calculation with Hubbard_parameters='file' ,
you meant you again performed vc-relax and then an scf, right?

Best regards,
Niharika

________________________________
From: kcbhamu85 at gmail.com<mailto:kcbhamu85 at gmail.com>
To: users at lists.quantum-espresso.org<mailto:users at lists.quantum-espresso.org>
Sent: Wednesday, November 24, 2021 1:02:31 PM
Subject: [QE-users] Need some comments on my U+V values obtained using        self-consistently

Dear Dr.  Lurii,
I could manage the HP code to obtain U+V value for my system.
Could you please comment on my approach and value obtained as mentioned below?


1. vc-relax with PBE (with all converged parameters of the input file, like ecut, k-points...).
2.(i): Using optimized geometry of step-1

calculation = 'relax' ;  nspin=2
  starting_magnetization(1) =   0.8;   starting_magnetization(2) =   -0.8 ;   starting_magnetization(3) =   0.0
  lda_plus_u = .true., ;   lda_plus_u_kind = 2, ;   U_projection_type = 'ortho-atomic',
  Hubbard_V(1,1,1) = 1.d-8;   Hubbard_V(2,2,1) = 1.d-8 ;   Hubbard_V(3,3,1) = 1.d-8
!   Hubbard_parameters = 'file'

head pwscf.Hubbard_parameters.dat
site n.  type  label  spin  new_type  new_label  Hubbard U (eV)
         1        1    Fe1     1      1         Fe1        4.6800
         2        1    Fe1     1      1         Fe1        4.6800
         3        1    Fe1     1      1         Fe1        4.6800
         4        1    Fe1     1      1         Fe1        4.6795

grep '1        1' parameters.out
dir1/parameters.out:     1        1       4.6800

2.(ii) In a fresh directory with parameters.in<http://parameters.in> of previous step.
kept all the parameters as such except
 !  Hubbard_V(1,1,1) = 1.d-8;   !   Hubbard_V(2,2,1) = 1.d-8 ;   !  Hubbard_V(3,3,1) = 1.d-8
Hubbard_parameters = 'file'

head pwscf.Hubbard_parameters.dat
site n.  type  label  spin  new_type  new_label  Hubbard U (eV)
         1        1    Fe1     1      1         Fe1        5.0513
         2        1    Fe1     1      1         Fe1        5.0513
         3        1    Fe1     1      1         Fe1        5.0513
         4        1    Fe1     1      1         Fe1        5.0514
grep '1        1' parameters.out
parameters.out:     1        1       5.0513

2.(iii) In a fresh directory with parameters.in<http://parameters.in> of previous step.
kept all the parameters as such except
 !   Hubbard_V(1,1,1) = 1.d-8;   !   Hubbard_V(2,2,1) = 1.d-8 ;   !   Hubbard_V(3,3,1) = 1.d-8
Hubbard_parameters = 'file'
head pwscf.Hubbard_parameters.dat
site n.  type  label  spin  new_type  new_label  Hubbard U (eV)
         1        1    Fe1     1      1         Fe1        5.0651
         2        1    Fe1     1      1         Fe1        5.0651
         3        1    Fe1     1      1         Fe1        5.0651
         4        1    Fe1     1      1         Fe1        5.0651

grep '1        1' parameters.out
parameters.out:     1        1       5.0651



  1.  Do you think, I have followed a correct approach to get the converged U+V value?
  2.  Do you think, the value I obtained for U+V is a converged value?

I am looking forward to hearing from you.

Regards
Bhamu





_______________________________________________
Quantum ESPRESSO is supported by MaX (www.max-centre.eu<http://www.max-centre.eu>)
users mailing list users at lists.quantum-espresso.org<mailto:users at lists.quantum-espresso.org>
https://lists.quantum-espresso.org/mailman/listinfo/users


_______________________________________________
Quantum ESPRESSO is supported by MaX (www.max-centre.eu<http://www.max-centre.eu>)
users mailing list users at lists.quantum-espresso.org<mailto:users at lists.quantum-espresso.org>
https://lists.quantum-espresso.org/mailman/listinfo/users
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20211124/280991f4/attachment.html>


More information about the users mailing list