My Community

Dear Admin,

This is the input in my INCAR file.
PREC = Accurate
ICHARG = 2
IBRION = 2
NSW = 0
LNONCOLLINEAR = .TRUE.
MAGMOM = 144*0 0 0 1 0 0 -1 0 0 -1 0 0 1
LREAL = Auto
LVTOT = .TRUE.
LELF = .TRUE.
LAECHG = .TRUE.
LCHARG = .TRUE.
LORBIT = 11
EMIN = -20
EMAX = 15
NEDOS = 5250
ISMEAR = 0
SIGMA = 0.01
LVHAR = .TRUE.
ALGO = FAST

I am calculating for CeRu2Al10 to know the DOS and the spin direction after relaxation.
There are 4 Cerium in the unitcell. After the calculation has finished, I analyze the result and found that
by running NEDOS = 3500, the spin direction was at c-axis, 0.06 -0.06 -0.06 0.06.
But, when I change to NEDOS = 5250, the spin change to -0.072 0.072 0.072 -0.07 (180 degrees flip)
But, it changed again to 0.06 -0.06 -0.06 0.06 after I increased the NEDOS to be 7000. *again 180 degrees flip*

Would you suggest me any idea why it is happening?
Why the NEDOS could change the spin direction and the magnetic moment value?
I though NEDOS only change the DOS resolution.
Sorry for my bad english.

Thank you.

The system is quite large, the calculated spin values are small, and if you use just
the default precision this fluctuation of spin values is nothing but numerical noise.