constraint spin direction fails

[ktao]

Hi, all,

I want to constraint the spin direction of atoms in a cluster to different directions, however, finally, the spin direction of atoms change to another direction. In other words, the constraint fails. Could anyone give me some suggestions?

My input file is following:

ISTART = 0
NWRITE = 2 : verbosity

ICHARG = 11

ENCUT = 400

# EMIN = -13.2
# EMAX = 3.8
# NEDOS = 1001

ADDGRID = .TRUE.

PREC = accurate : accuracy
NELM = 300 : maximum number of SCF iterations
NELMIN = 12 : minimal number of SCF iterations
NELMDL = -6 : number of non-SCF iterations
EDIFF = 1E-7 : criterion for SCF convergence
ISMEAR = 1 : Methfessel-Paxton smearing
SIGMA = 0.01 : sigma for smearing

NPAR = 1

GGA = PE
GGA_COMPAT = .FALSE.
VOSKOWN = 1

ALGO = Normal

ISPIN = 2
MAGMOM = 0 0 12 11.4 3.72 6 0 12 6 -11.4 3.72 6 -7.10 -9.80 6 7.10 -9.80 6 0 0 12 7.10 9.80 6 -7.10 9.80 6 -11.4 -3.72 6 0 -12 6 11.4 -3.72 6 0 0 12

I_CONSTRAINED_M = 1
RWIGS = 1.0
LAMBDA = 100
M_CONSTR = 0 0 1 0.95 0.31 0.5 0 1 0.5 -0.95 0.31 0.5 -0.59 -0.81 0.5 0.59 -0.81 0.5 0 0 1 0.59 0.81 0.5 -0.59 0.81 0.5 -0.95 -0.31 0.5 0 -1 0.5 0.95 -0.31 0.5 0 0 1

LNONCOLLINEAR= .TRUE.

LORBIT = 11

NBANDS = 560 ### 1.5 NBANDS

####################################
# Parameters for SOC
ISYM = 0
LMAXMIX = 6
LSORBIT = .TRUE.
LORBMOM = .TRUE.
SAXIS = 0 0 1

####################################
# Ionic Relaxation
NSW = 0 : maximum number of ionic steps
EDIFFG = -1.0E-2 : maximal residual force in eV/Ang
IBRION = 1 : quasi-Newton optimization
ISIF = 0 : optimize ions, cell shape and volume

[support_vasp]

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