ISPIN
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. This is important for magnetic systems, where the two spin channels can have different occupations and energies. For nonmagnetic systems, spin polarization is often unnecessary and a non-spin-polarized calculation is sufficient.
- ISPIN=1: non-spin-polarized calculations are performed. The spin-up and spin-down electrons are treated as identical.
- ISPIN=2: spin-polarized collinear calculations are performed. The 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.
| Important: For noncollinear calculations ISPIN is ignored. In VASP 6.5.0, the calculation exits with an error message if ISPIN=2 and MAGMOM are used together with LNONCOLLINEAR=.TRUE. |