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Difference between revisions of "Including the Spin-Orbit Coupling"

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Description: Spin-Orbit Coupling (SOC) included self-consistently
 
Description: Spin-Orbit Coupling (SOC) included self-consistently
  
The Magnetocrystalline Anisotropy Energy is determined by rotating all spins according to different directions. To modify the orientation of the spins in the crystal, we consider the second approach described in the [[SAXIS|SAXIS]] page. For the [[MAGMOM|MAGMOM]]-tag, the total local magnetic moment is written according to the z direction (necessarily, the x and y-directions are equal to 0). The spin orientation [uvw] is defined by the [[SAXIS|SAXIS]]-tag in the Cartesian frame. 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.
+
The Magnetocrystalline Anisotropy Energy is determined by rotating all spins according to different directions. To modify the orientation of the spins in the crystal, we consider the second approach described [[SAXIS|here]]. For the [[MAGMOM|MAGMOM]]-tag, the total local magnetic moment is written according to the z-direction (necessarily, the x and y-directions are equal to 0). The spin orientation <math>(u,v,w)</math> is defined by the [[SAXIS|SAXIS]]-tag in the Cartesian frame. The Magnetocrystalline Anisotropy Energy is calculated by orientating the spins in different directions and the following equation
  
 +
::<math>E_{\text{MAE}} = E_{(u,v,w)} - E_0</math>
 +
 +
with <math>E_0</math> the energy of the most stable spin orientation.
  
 
More details are available in the [[SAXIS|SAXIS]] and [[LSORBIT|LSORBIT]] pages.
 
More details are available in the [[SAXIS|SAXIS]] and [[LSORBIT|LSORBIT]] pages.

Latest revision as of 17:43, 8 February 2021

Description: Spin-Orbit Coupling (SOC) included self-consistently

The Magnetocrystalline Anisotropy Energy is determined by rotating all spins according to different directions. To modify the orientation of the spins in the crystal, we consider the second approach described here. For the MAGMOM-tag, the total local magnetic moment is written according to the z-direction (necessarily, the x and y-directions are equal to 0). The spin orientation is defined by the SAXIS-tag in the Cartesian frame. The Magnetocrystalline Anisotropy Energy is calculated by orientating the spins in different directions and the following equation

with the energy of the most stable spin orientation.

More details are available in the SAXIS and LSORBIT pages.

Exercise : Determine the total magnetic moment by adding the orbital moment of the Ni atoms. Calculate the Magnetocrystalline Anisotropy Energy of NiO by orientating the spins along the following path : (2,2,2) --> (2,2,1) --> (2,2,0) --> ... --> (2,2,-6). Identify the most stable spin orientation according to this path.


NiO GGA+U SOC
 SYSTEM    = "NiO"
    
Electronic minimization
  ENCUT     = 450
  EDIFF     = 1E-7
  LORBIT    = 11
  LREAL     = .False.
  ISTART    = 0
  ISYM      = -1
  NELMIN    = 6
  LSORBIT   = .True.
  LWAVE     = .False.
  LCHARG    = .False.
    
DOS
  ISMEAR    = -5
     
Magnetism
  ISPIN     = 2
  MAGMOM    = 0 0 2 0 0 -2 6*0
  SAXIS     = 2 2 2
     
Orbital Moment
  LORBMOM   = T 
     
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 
k-points
 0
gamma
 4  4  4 
 0  0  0
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

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nio_SOC.tgz