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Dear Vasp users,
I'm doing a single-point broken-symmetry DFT calculation of a [Co3(pytag)(py)6Cl3]+ cationic molecule. Here each Co center is in +II, d7, high-spin state. However the broken symmetry state (Co1; S = 3/2, Co2; S = 3/2, Co3; S= -3/2) is the ground state. I'm using the following INCAR file
SYSTEM = Co3_BS1
ISTART = 0
ICHARG = 2
NCORE = 16
NSW = 0
EDIFF = 1E-05
LREAL = AUTO
ISMEAR = 0
PREC = Medium
SIGMA = 0.01
NELM = 300
ALGO = FAST
ISPIN = 2
NELECT = 363
MAGMOM = 1*3.90 1*3.90 1*-3.90 3*0 15*0 49*0 45*0
LORBIT = 11
For the broken symmetry state, we expect spin densities on Co1, Co2, and Co3 around 3.0, 3.0, and -3.0 respectively. However, in the OUTCAR file, the spin densities are coming around 0.989, 1.105, and 1.018. Can anyone please let me know what are the corrections needed to get the correct spin densities?

Dear Rajaraman,

Your system might require a DFT+U treatment (probably a U>0 on Co) to reach a specific solution.
However, we can tell you more, if you provide a proper error report.

Hello Rajaraman,

two things you might consider:
a) spin densities are computed with the help of alpha and beta charge (!) densities (alpha - beta).
Since charges are not localized, you will probably never see the desired spin in spin densities. ~0.5e for one electron is in my experience a good indication. But be careful with that.
b) check OSZICAR for the magnetic moment, here you'll see if you reach the proper value for your system.

Best regards,

alex