Determining the Magnetic Anisotropy: Difference between revisions

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Description: Magnetocrystalline Anisotropy Energy
Description: Magnetocrystalline Anisotropy Energy
The Magnetocrystalline Anisotropy Energy is determined by rotating all spins according different directions. First of all, an accurate ([[PREC|PREC]] = Accurate, [[LREAL|LREAL]] = .False.) collinear calculation in the ground state has to be done because of the very low changes in measured energies (sometimes, it could be about the micro-eV). After that, the Spin-Orbit Coupling is took into account non-self-consistently ([[ICHARG|ICHARG]] = 11).


----
----
*INCAR
*INCAR
<pre>
<pre>
NiO GGA+U MAE
NiO MAE
   SYSTEM    = "NiO"
   SYSTEM    = "NiO"


Electronic minimization
Electronic minimization
  PREC = Accurate
   ENCUT        = 450
   ENCUT        = 450
   EDIFF        = 1E-7
   EDIFF        = 1E-7
   LORBIT        = 11
   LORBIT        = 11
   LREAL        = .False.
   LREAL        = .False.
  ISTART        = 0
   ISYM          = -1
   ISYM          = -1
   NELMIN        = 6
   NELMIN        = 6
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   #  LCHARG = .FALSE.
   #  LCHARG = .FALSE.
   #  LWAVE = .FALSE.
   #  LWAVE = .FALSE.
   #  NBANDS = 328
   #  NBANDS = 52
   #  GGA_COMPAT = .FALSE.
   #  GGA_COMPAT = .FALSE.


Line 26: Line 28:
Magnetism
Magnetism
   ISPIN    = 2
   ISPIN    = 2
   MAGMOM    = 0 0 2 0 0 -2 6*0 # Ground state
   MAGMOM = 2.0 -2.0 2*0.0
  # MAGMOM    = 0 0 2 0 0 -2 6*0 # Including Spin-orbit
   # LSORBIT      = .True.
   # LSORBIT      = .True.
   # LNONCOLLINEAR = .True.
   # LNONCOLLINEAR = .True.
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</pre>
</pre>
----
----
Firstly, a collinear calculation has to be done. The magnetic anisotropy is determined non-self-consistently by rotating all spins according to a defined direction (uvw). The Magnetocrystalline Anisotropy Energy is calculated by orientating the spins in different directions and the following equation : EMAE = E(uvw) - Emin, with Emin the energy of the most stable spin orientation.
Firstly, a collinear calculation has to be done. The magnetic anisotropy is determined non-self-consistently by rotating all spins according to a defined direction [uvw]. The Magnetocrystalline Anisotropy Energy is calculated by orientating the spins in different directions and the following equation : E<sub>MAE</sub> = E<sub>[uvw]</sub> - E<sub>min</sub>, with E<sub>min</sub> the energy of the most stable spin orientation.


== Download ==
== Download ==

Revision as of 13:38, 25 August 2016

Description: Magnetocrystalline Anisotropy Energy

The Magnetocrystalline Anisotropy Energy is determined by rotating all spins according different directions. First of all, an accurate (PREC = Accurate, LREAL = .False.) collinear calculation in the ground state has to be done because of the very low changes in measured energies (sometimes, it could be about the micro-eV). After that, the Spin-Orbit Coupling is took into account non-self-consistently (ICHARG = 11).


  • INCAR
NiO MAE
  SYSTEM    = "NiO"

Electronic minimization
  PREC = Accurate
  ENCUT         = 450
  EDIFF         = 1E-7
  LORBIT        = 11
  LREAL         = .False.
  ISYM          = -1
  NELMIN        = 6
  #  ICHARG = 11
  #  LCHARG = .FALSE.
  #  LWAVE = .FALSE.
  #  NBANDS = 52
  #  GGA_COMPAT = .FALSE.

DOS
  ISMEAR    = -5

Magnetism
  ISPIN     = 2
  MAGMOM = 2.0 -2.0 2*0.0
  # MAGMOM    = 0 0 2 0 0 -2 6*0 # Including Spin-orbit
  # LSORBIT       = .True.
  # LNONCOLLINEAR = .True.
  # SAXIS = 1 0 0 # Quantization axis used to rotate all spins in a direction defined in the (O,x,y,z) Cartesian frame

Mixer
  AMIX      = 0.2
  BMIX      = 0.00001
  AMIX_MAG  = 0.8
  BMIX_MAG  = 0.00001

GGA+U
  LDAU      = .TRUE.
  LDAUTYPE  = 2
  LDAUL     = 2 -1
  LDAUU     = 5.00 0.00
  LDAUJ     = 0.00 0.00
  LDAUPRINT = 2
  LMAXMIX   = 4 
  • KPOINTS
k-points
 0
gamma
 4  4  4 
 0  0  0
  • POSCAR
NiO
 4.17
 1.0 0.5 0.5
 0.5 1.0 0.5
 0.5 0.5 1.0
 2 2
Cartesian
 0.0 0.0 0.0
 1.0 1.0 1.0
 0.5 0.5 0.5
 1.5 1.5 1.5

Firstly, a collinear calculation has to be done. The magnetic anisotropy is determined non-self-consistently by rotating all spins according to a defined direction [uvw]. The Magnetocrystalline Anisotropy Energy is calculated by orientating the spins in different directions and the following equation : EMAE = E[uvw] - Emin, with Emin the energy of the most stable spin orientation.

Download

4_3_NiO_LSDA+U.tgz


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