Constraining the direction of magnetic moments
Posted: Sat Mar 01, 2014 1:22 am
Dear VASP Users,
I need to do calculations of FCC Fe system with several defects in the ferro-magnetic states. It was not a problem for perfect system without a defect. But, if I induced defects such as vacancy, interstitial and substitution, the systems are no-longer ferro-magnetic.
To constrain the direction of moments, I already tried non-collinear tags as suggested in the manual (http://cms.mpi.univie.ac.at/vasp/vasp/C ... ments.html). But it doesn?t help. Although moments are constrained to z-direction, but moments of several atoms were flipped over. For example, I want to set the moments of all Fe atoms to be (0 0 X). But moments of some atoms were converged to (0 0 ?X) even I used the non-collinear tags as shown below. Is this the typical results even I use the non-collinear tags? Or did I do something wrong?
thanks for your comments!
Hyo
Tags that I used...
LNONCOLLINEAR = .TRUE.
MAGMOM = 0 0 2 0 0 2?
I_CONSTRAINED_M = 1
RWIGS = 1.0
LAMDA = 10
M_CONSTR = 0 0 1 0 0 1 ?
I need to do calculations of FCC Fe system with several defects in the ferro-magnetic states. It was not a problem for perfect system without a defect. But, if I induced defects such as vacancy, interstitial and substitution, the systems are no-longer ferro-magnetic.
To constrain the direction of moments, I already tried non-collinear tags as suggested in the manual (http://cms.mpi.univie.ac.at/vasp/vasp/C ... ments.html). But it doesn?t help. Although moments are constrained to z-direction, but moments of several atoms were flipped over. For example, I want to set the moments of all Fe atoms to be (0 0 X). But moments of some atoms were converged to (0 0 ?X) even I used the non-collinear tags as shown below. Is this the typical results even I use the non-collinear tags? Or did I do something wrong?
thanks for your comments!
Hyo
Tags that I used...
LNONCOLLINEAR = .TRUE.
MAGMOM = 0 0 2 0 0 2?
I_CONSTRAINED_M = 1
RWIGS = 1.0
LAMDA = 10
M_CONSTR = 0 0 1 0 0 1 ?