My Community

I want to perform geometry optimization on a crystal structure with/without different magnetic structure type(collinear spin).

Some magnetic type can be achieved by directly adding magnetic moment to the atoms in the unit cell.(use MAGMOM on original POSCAR)

Others need a double or quadruple supercell in different directions(use MAGMON on a supercell POSCAR generated from the original POSCAR)

But for supercell, VASP seems can not detect the correct symmetry of supercell automatically as the unit cell.

So, my question is how can I perform the calculation on the supercell which has the same space group structure of unit cell but just has some different magnetic structure?

Can I set some symmetry restrictions on my crystal structure by hand?

PS: In my study, I assume the magnetic moment doesn't break the symmetry of the original non-magnetic one, just cause relaxation of lattice parameters and displacement of atoms inside the unitcell.
<span class='smallblacktext'>[ Edited ]</span>

if the symmetry is not broken by the magnetic moments, it maybe is by the relaxed lattice parameters or the displacement pattern of the atoms?
please also mind that a 2x1x1 supercell of a cubic unit cell is tertagonal (from the symmetry analysis of the Bravais matrix).
In general, symmetry analysis includes 4 steps in vasp:
from POSCAR
1) the Bravais Matrix
2) the positions of the ions
(3) the initial velocities of the ions, if given)
from INCAR
(4) the magnetic moments, if given). Please keep in mind that eg. antiferromagnetic spin alignment also may reduce the symmetry of the cell.
it may be helpful if you show 2 POSCAR examples