LNONCOLLINEAR = .TRUE. | .FALSE.
Default: LNONCOLLINEAR = .FALSE.
Description: LNONCOLLINEAR specifies whether fully non-collinear magnetic calculations are performed.
Supported as of VASP.4.5.
Setting LNONCOLLINEAR = .TRUE. in the INCAR file allows to perform fully non-collinear magnetic structure calculations. VASP is capable of reading WAVECAR and CHGCAR files from previous non-magnetic or collinear calculations, it is however not possible to rotate the magnetic field locally on selected atoms.
Hence, in practice, we recommend to perform non-collinear calculations in two steps:
- First, calculate the non magnetic groundstate and generate a WAVECAR and CHGCAR file.
- Second, read the WAVECAR and CHGCAR file, and supply initial magnetic moments by means of the MAGMOM tag (compare MAGMOM).
For a non-collinear setup, three values must be supplied for each ion in the MAGMOM line. The three entries correspond to the initial local magnetic moment for each ion in x, y and z direction respectively. The line
MAGMOM = 1 0 0 0 1 0
initialises the magnetic moment on the first atom in the x-direction, and on the second atom in the y direction. Mind, that the MAGMOM line supplies initial magnetic moments only if ICHARG = 2, or if the CHGCAR file contains only charge but no magnetisation density.