Hello all,
I set up a calculation for a Fe dimer with spin-orbit coupling starting from the geometry and charge density of a collinear calculation. Everything goes on fine but at the end it gives me that the easy axis is along the perpendicular (x) direction to the dimer axis. Am I doing something wrong or is it just a matter of misunderstanding the VASP results? Here is the input file for the SOC calculation along the z axis:
SYSTEM = Fe2
LWAVE = .TRUE.
LCHARG = .FALSE.
ISPIN = 2
LMAXMIX = 4
IBRION = 2
NSW = 250
NELM = 250
NELMDL = 6
EDIFF = 0.00000001
EDIFFG = -0.005
PREC = Accurate
ENMAX = 575
AMIX = 0.2
BMIX = 0.0001
AMIX_MAG = 0.8
BMIX_MAG = 0.0001
ISMEAR = 0
SIGMA = 0.02
NBANDS = 40
RWIGS = 0.98
ADDGRID = .TRUE.
LORBIT = 11
ALGO = Fast
NPAR = 8
NSIM = 8
LSORBIT = .TRUE.
ICHARG = 1
ISYM = 0
SAXIS = 0 0 1
MAGMOM = 0 0 3 0 0 3
LORBMOM = .TRUE.
And here is for the x axis:
SYSTEM = Fe2
LWAVE = .TRUE.
LCHARG = .FALSE.
ISPIN = 2
LMAXMIX = 4
IBRION = 2
NSW = 250
NELM = 250
NELMDL = 6
EDIFF = 0.00000001
EDIFFG = -0.005
PREC = Accurate
ENMAX = 575
AMIX = 0.2
BMIX = 0.0001
AMIX_MAG = 0.8
BMIX_MAG = 0.0001
ISMEAR = 0
SIGMA = 0.02
NBANDS = 40
RWIGS = 0.98
ADDGRID = .TRUE.
LORBIT = 11
ALGO = Fast
NPAR = 8
NSIM = 8
LSORBIT = .TRUE.
ICHARG = 1
ISYM = 0
SAXIS = 1 0 0
MAGMOM = 0 0 3 0 0 3
LORBMOM = .TRUE.
The calculation with the quantization axis along the z axis gives the following results:
FREE ENERGIE OF THE ION-ELECTRON SYSTEM (eV)
---------------------------------------------------
free energy TOTEN = -9.446615 eV
energy without entropy= -9.446615 energy(sigma->0) = -9.446615
orbital moment (x)
# of ion p d tot
----------------------------------------
1 0.000 0.000 0.000
2 0.000 0.000 0.000
----------------------------------------
0.000 0.000 0.000
orbital moment (y)
# of ion p d tot
----------------------------------------
1 0.000 0.000 0.000
2 0.000 0.000 0.000
----------------------------------------
0.000 0.000 0.000
orbital moment (z)
# of ion p d tot
----------------------------------------
1 0.000 0.130 0.130
2 0.000 0.130 0.130
----------------------------------------
0.000 0.260 0.260
magnetization (x)
# of ion s p d tot
----------------------------------------
1 0.000 0.000 0.000 0.000
2 0.000 0.000 0.000 0.000
------------------------------------------------
tot 0.000 0.000 0.000 0.000
magnetization (y)
# of ion s p d tot
----------------------------------------
1 0.000 0.000 0.000 0.000
2 0.000 0.000 0.000 0.000
------------------------------------------------
tot 0.000 0.000 0.000 0.000
magnetization (z)
# of ion s p d tot
----------------------------------------
1 0.048 -0.006 2.776 2.818
2 0.048 -0.006 2.776 2.818
------------------------------------------------
tot 0.097 -0.012 5.553 5.637
while the calculation along the perpendicular (x) direction gives:
FREE ENERGIE OF THE ION-ELECTRON SYSTEM (eV)
---------------------------------------------------
free energy TOTEN = -9.447210 eV
energy without entropy= -9.447210 energy(sigma->0) = -9.447210
orbital moment (x)
# of ion p d tot
----------------------------------------
1 -0.001 0.080 0.080
2 -0.001 0.080 0.080
----------------------------------------
-0.001 0.161 0.160
orbital moment (y)
# of ion p d tot
----------------------------------------
1 0.000 0.000 0.000
2 0.000 0.000 0.000
----------------------------------------
0.000 0.000 0.000
orbital moment (z)
# of ion p d tot
----------------------------------------
1 0.000 0.000 0.000
2 0.000 0.000 0.000
----------------------------------------
0.000 0.000 0.000
total charge
# of ion s p d tot
----------------------------------------
1 0.478 0.095 6.388 6.961
2 0.478 0.095 6.388 6.961
------------------------------------------------
tot 0.955 0.191 12.776 13.922
magnetization (x)
# of ion s p d tot
----------------------------------------
1 0.000 0.000 0.000 0.000
2 0.000 0.000 0.000 0.000
------------------------------------------------
tot 0.000 0.000 0.000 0.000
magnetization (y)
# of ion s p d tot
----------------------------------------
1 0.000 0.000 0.000 0.000
2 0.000 0.000 0.000 0.000
------------------------------------------------
tot 0.000 0.000 0.000 0.000
magnetization (z)
# of ion s p d tot
----------------------------------------
1 0.048 -0.006 2.776 2.818
2 0.048 -0.006 2.776 2.818
------------------------------------------------
tot 0.097 -0.012 5.551 5.636
Thank you for you kind help.
- Jose Luis
What am I doing wrong?
Moderators: Global Moderator, Moderator
-
jlrch
- Newbie
- Posts: 26
- Joined: Tue Jun 14, 2005 5:18 pm
What am I doing wrong?
Last edited by jlrch on Mon Oct 24, 2011 8:48 pm, edited 1 time in total.
-
support_vasp
- Global Moderator
- Posts: 1817
- Joined: Mon Nov 18, 2019 11:00 am
Re: What am I doing wrong?
Hi,
We're sorry that we didn’t answer your question. This does not live up to the quality of support that we aim to provide. The team has since expanded. If we can still help with your problem, please ask again in a new post, linking to this one, and we will answer as quickly as possible.
Best wishes,
VASP