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{{TAGDEF|ISPIN|1 {{!}} 2|1}}
{{TAGDEF|ISPIN|1 {{!}} 2|1}}


Description: {{TAG|ISPIN}} specifies spin polarization.
Description: {{TAG|ISPIN}} specifies whether a calculation is performed with or without spin polarization.
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*{{TAG|ISPIN}}=1: non spin polarized calculations are performed.
In spin-polarized calculations, VASP treats spin-up and spin-down electrons separately, allowing each spin channel to develop a different charge density and occupation. This is essential for magnetic systems; for nonmagnetic systems it is generally unnecessary and increases computational cost.
*{{TAG|ISPIN}}=2: spin polarized calculations (collinear) are performed.


By combining {{TAG|ISPIN}} with {{TAG|MAGMOM}} collinear magnetism can be studied.
*{{TAG|ISPIN}}=1: VASP performs a non-spin-polarized calculation. Spin-up and spin-down electrons share a single charge density.


== Related Tags and Sections ==
*{{TAG|ISPIN}}=2: VASP performs a spin-polarized collinear calculation. Spin-up and spin-down electrons are treated separately.
{{TAG|MAGMOM}}
 
Spin-polarized calculations are commonly used for magnetic materials such as Fe, Co, Ni, and magnetic oxides. To initialize magnetic moments on atoms, combine {{TAG|ISPIN}}=2 with {{TAG|MAGMOM}}.
 
ISPIN = 2
MAGMOM = 2*5.0 2*-5.0
 
This example initializes two atoms with positive magnetic moments and two atoms with negative magnetic moments, which may be useful for antiferromagnetic calculations.


== Example Calculations using this Tag ==
{{NB|mind|For noncollinear calculations, {{TAG|ISPIN}} is ignored; use {{TAG|LNONCOLLINEAR}}{{=}}.TRUE. instead.|:}}
{{TAG|Fcc Ni}}, {{TAG|Fcc Ni (revisited)}}, {{TAG|Fcc Ni DOS}}, {{TAG|Fcc Ni DOS with hybrid functional}}, {{TAG|Ni 100 surface bandstructure}}, {{TAG|Ni 100 surface relaxation}}, {{TAG|NiO}}, {{TAG|NiO LSDA+U}}, {{TAG|O atom spinpolarized}}, {{TAG|O atom spinpolarized low symmetry}}, {{TAG|O dimer}}


{{NB|mind|Since VASP 6.5.0, the calculation exits with an error if {{TAG|ISPIN}}{{=}}2 and {{TAG|MAGMOM}} are used together with {{TAG|LNONCOLLINEAR}}{{=}}.TRUE.|:}}


== Related tags and articles ==
{{TAG|MAGMOM}}
{{TAG|LNONCOLLINEAR}}


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{{sc|ISPIN|Howto|Examples that use this tag}}
[[The_VASP_Manual|Contents]]


[[Category:INCAR]][[Category:Magnetism]]
[[Category:INCAR tag]][[Category:Magnetism]]

Latest revision as of 14:20, 1 June 2026

ISPIN = 1 | 2
Default: ISPIN = 1 

Description: ISPIN specifies whether a calculation is performed with or without spin polarization.


In spin-polarized calculations, VASP treats spin-up and spin-down electrons separately, allowing each spin channel to develop a different charge density and occupation. This is essential for magnetic systems; for nonmagnetic systems it is generally unnecessary and increases computational cost.

  • ISPIN=1: VASP performs a non-spin-polarized calculation. Spin-up and spin-down electrons share a single charge density.
  • ISPIN=2: VASP performs a spin-polarized collinear calculation. Spin-up and spin-down electrons are treated separately.

Spin-polarized calculations are commonly used for magnetic materials such as Fe, Co, Ni, and magnetic oxides. To initialize magnetic moments on atoms, combine ISPIN=2 with MAGMOM.

ISPIN = 2
MAGMOM = 2*5.0 2*-5.0

This example initializes two atoms with positive magnetic moments and two atoms with negative magnetic moments, which may be useful for antiferromagnetic calculations.



Related tags and articles

MAGMOM LNONCOLLINEAR

Examples that use this tag