Constraining the local magnetic moments: Difference between revisions

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Description: Constraining the local magnetic moments on NiO.
Description: Constraining the local magnetic moments on NiO.


To orientate locally each spin, a penalty energy E<sub>p</sub> is added, inversely proportional to the LAMBDA parameter. Thus, the process has to begin with a low LAMBDA, which is increased step by step.
To orient locally each spin, a penalty energy <math>E_p</math> is added, inversely proportional to the <math>\lambda</math> ([[LAMBDA]]) parameter. Thus, the process has to begin with a low [[LAMBDA]], which is increased step by step.


For additional informations, go to the [[I_CONSTRAINED_M|I_CONSTRAINED_M]] page.
For additional information, go to the [[I_CONSTRAINED_M|I_CONSTRAINED_M]] page.


''<u>Exercise :</u>'' Verify the E<sub>p</sub>=f(1/LAMBDA) relation by constraining the spin directions. Check the efficiency of the method by constraining only the direction, then the direction and the size of spins.
''<u>Exercise :</u>'' Verify the <math>E_p=f(1/\lambda)</math> relation by constraining the spin directions. Check the efficiency of the method by constraining only the direction, then the direction and the size of spins.


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Revision as of 08:53, 4 February 2021

Description: Constraining the local magnetic moments on NiO.

To orient locally each spin, a penalty energy is added, inversely proportional to the (LAMBDA) parameter. Thus, the process has to begin with a low LAMBDA, which is increased step by step.

For additional information, go to the I_CONSTRAINED_M page.

Exercise : Verify the relation by constraining the spin directions. Check the efficiency of the method by constraining only the direction, then the direction and the size of spins.


NiO GGA+U Constr.
  SYSTEM        = "NiO"
   
Electronic minimization
  ENCUT         = 450
  EDIFF         = 1E-5
  LORBIT        = 11
  LREAL         = .False.
  ISYM          = -1
  NELMIN        = 6
  LSORBIT       = .True.
  GGA_COMPAT    = .FALSE.
   
DOS
  ISMEAR    = -5
   
Magnetism
  ISPIN     = 2
  I_CONSTRAINED_M = 1  # direction
  # I_CONSTRAINED_M = 2  # size and direction
  M_CONSTR  = 2 0 0 0 -2 0 6*0
  LAMBDA    = 1
  RWIGS     = 1.30 0.70 
    
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_constr.tgz