I have been trying to calculate the magnetic ground state of NdBi. The magnetic moment from INFO.OUT is around 2 μB for Nb atom, but it is about 4 μB according to the experiments. I also tried to change xctype to 3 or 21, which both get much smaller magnetic moments. Are there any solutions could be suggested to calculate the magnetic moment of f electron, please?
I would appreciate any help with regards to this issue. Thanks in advance!
Best regards,
Yilyu
! Antiferromagnetic fcc iron example
tasks
0
15
rgkmax
9
xctype
20
spinpol
.true.
spinorb
.true.
wrtdsk
.false.
! fairly large number of empty states required for magnetic cases
nempty
6
autolinengy
.true.
tshift
.false.
sppath
'~/workspace/22-11/elk/species/'
! DFT+U block
! here AMF double counting is used (dftu=2)
! inpdftu=1 corresponds to provide U and J as input
dft+u
1 1 : dftu, inpdftu
1 3 0.2315206456307199 0.0257245161811911 : is, l, U, J
avec
4.53255446740577 0.00000 0.00000
0.00000 4.53255446740577 0.00000
0.00000 0.00000 6.41
Thanks for your quick reply. The effective U value (U = 6.3 eV and J = 0.7 eV for the strongly localized Nd 4f orbitals) is taken from the reference [Nature 2022, 603, 610–615. (https://www.nature.com/articles/s41586-022-04412-x)]. In their work, it shows a total magnetic moment of 3.1 µB on Nd.
When PBE+SOC+U (xctype 20) is applied, the magnetic moment of Nd is 2.18 µB. The elk.in file is as following.
Thanks and regards,
Yilyu
tasks
0
15
rgkmax
8
xctype
20
stype
0
swidth
0.001
spinpol
.true.
broydpm
0.04 0.01
mixtype
1
beta0
0.01
gmaxvr
20
epsband
1.e-12
lradstp
1
spinorb
.true.
wrtdsk
.false.
nempty
20
reducebf
0.5
sppath
'~/workspace/22-11/elk/species/'
dft+u
1 1 : dftu, inpdftu
1 3 0.2315206456307199 0.0257245161811911 : is, l, U, J
avec
4.53255446740577 0.00000 0.00000
0.00000 4.53255446740577 0.00000
0.00000 0.00000 6.41
Hi all,
I have been trying to calculate the magnetic ground state of NdBi. The magnetic moment from INFO.OUT is around 2 μB for Nb atom, but it is about 4 μB according to the experiments. I also tried to change xctype to 3 or 21, which both get much smaller magnetic moments. Are there any solutions could be suggested to calculate the magnetic moment of f electron, please?
I would appreciate any help with regards to this issue. Thanks in advance!
Best regards,
Yilyu
! Antiferromagnetic fcc iron example
tasks
0
15
rgkmax
9
xctype
20
spinpol
.true.
spinorb
.true.
wrtdsk
.false.
! fairly large number of empty states required for magnetic cases
nempty
6
autolinengy
.true.
tshift
.false.
sppath
'~/workspace/22-11/elk/species/'
! DFT+U block
! here AMF double counting is used (dftu=2)
! inpdftu=1 corresponds to provide U and J as input
dft+u
1 1 : dftu, inpdftu
1 3 0.2315206456307199 0.0257245161811911 : is, l, U, J
avec
4.53255446740577 0.00000 0.00000
0.00000 4.53255446740577 0.00000
0.00000 0.00000 6.41
scale
1.8897261339212518764104149343425
atoms
2 : nspecies
'Nd.in' : spfname
2 : natoms; atpos, bfcmt below
0.00000 0.00000 0.0000 0.00000000 0.00000000 -0.01000000
0.00000 0.5000 0.5000 0.00000000 0.00000000 0.01000000
'Bi.in' : spfname
2 : natoms; atpos, bfcmt below
0.5000 0.5000 0.0000 0.00000000 0.00000000 0.00000000
0.50000 0.0000 0.5000 0.00000000 0.00000000 0.00000000
!this k-point set is too small for calculation of accurate moments
ngridk
11 11 7
Hi Yilyu,
I recommend you use LDA+U by applying U to the Nd.
Best
Hi Sangeeta,
Did you mean use LDA as following?
xctype
100 1 9
(see https://sourceforge.net/p/elk/discussion/897820/thread/9d5f437546/)
I have also applied U To the Nd
dft+u
1 1 : dftu, inpdftu
1 3 0.2315206456307199 0.0257245161811911 : is, l, U, J
But the magnetic moment is 1.7 μB, much smaller than the experimental result.
Thanks
Yilyu
You could plot the moment as a function of U. Do you ever get numbers greater than 1.7 for a larger value of U?
Hi Sangeeta,
Thanks for your quick reply. The effective U value (U = 6.3 eV and J = 0.7 eV for the strongly localized Nd 4f orbitals) is taken from the reference [Nature 2022, 603, 610–615. (https://www.nature.com/articles/s41586-022-04412-x)]. In their work, it shows a total magnetic moment of 3.1 µB on Nd.
When PBE+SOC+U (xctype 20) is applied, the magnetic moment of Nd is 2.18 µB. The elk.in file is as following.
Thanks and regards,
Yilyu
tasks
0
15
rgkmax
8
xctype
20
stype
0
swidth
0.001
spinpol
.true.
broydpm
0.04 0.01
mixtype
1
beta0
0.01
gmaxvr
20
epsband
1.e-12
lradstp
1
spinorb
.true.
wrtdsk
.false.
nempty
20
reducebf
0.5
sppath
'~/workspace/22-11/elk/species/'
dft+u
1 1 : dftu, inpdftu
1 3 0.2315206456307199 0.0257245161811911 : is, l, U, J
avec
4.53255446740577 0.00000 0.00000
0.00000 4.53255446740577 0.00000
0.00000 0.00000 6.41
scale
1.8897261339212518764104149343425
atoms
2 : nspecies
'Nd.in' : spfname
2 : natoms; atpos, bfcmt below
0.00000 0.00000 0.0000 0.00000000 0.00000000 -7.01000000
0.50000 0.5000 0.5000 0.00000000 0.00000000 7.01000000
'Bi.in' : spfname
2 : natoms; atpos, bfcmt below
0.5000 0.5000 0.0000 0.00000000 0.00000000 0.00000000
0.0000 0.0000 0.5000 0.00000000 0.00000000 0.00000000
ngridk
11 11 7