[Vasp] How to calculate the magnetic exchange parameter of Nickel Oxide NiO

 

We will calculate the J2 parameter which represents the superexchange coupling between the next nearest neighbors (d_Ni-Ni = 4.17 A)using the GGA+U method.

We need to do a ferromagnetic and antiferromagnetic calculations and calculate the J2 parameter through a formula.

Ferromagnetic calculation

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

  INCAR

NiO GGA+U AFM
  SYSTEM    = "NiO"

Electronic minimization
  ENCUT     = 450
  EDIFF     = 1E-4
  LORBIT    = 11
  LREAL     = .False.
  ISTART    = 0
  ISYM      = 0
  NELMIN    = 6

DOS
  ISMEAR    = -5

Magnetism
  ISPIN     = 2
  MAGMOM    = 2*2.0 2*0  # FM conf.

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

 

https://vasp-algerien1970.blogspot.com/2022/03/calculation-of-magnetic-exchange.html