I am planning to use the finite displacement method for calculating phonon spectrum, and I have prepared the INCAR file below to try it on a transition metal trihalide monolayer (e.g., VI$_3$). I would be very grateful if you could please check it and tell me what I should add/omit, and if you recommend following this Phonopy tutorial.
INCAR:
NPAR = 6
# Self Consistent Calculation step:
ISTART = 0
ICHARG = 2
#Electronic Relaxation:
ENCUT = 550 eV
EDIFF = 1.0E-8
PREC = Accurate
LREAL = .FALSE.
IALGO = 38
ADDGRID=.TRUE.
LCHARG = .FALSE.
LWAVE = .FALSE.
#Phonons
IBRION = -1
#Relaxation:
ISMEAR = 0
SIGMA = 0.05
NSW = 1
GGA_COMPAT = .FALSE.
# Magnetism:
ISPIN= 2
MAGMOM = 4*-5.0 4*5.0 24*0.6
LASPH = .TRUE.
LMAXMIX = 4
VOSKOWN = 1
#Mixer
AMIX = 0.2
BMIX = 0.00001
AMIX_MAG = 0.8
BMIX_MAG = 0.00001
I am a little bit confused about which IBRION tag to use (IBRION=-1 or IBRION=6)