C-type antiferromagnetism
Posted: Fri Aug 19, 2011 10:02 am
Hi, I have a difficulty calculating DOSCAR for LaMnO3.
As to Mn in orthorhombic LaMnO3, there are 3 types of antimagnetism possible to exist : A-, C-, G- which have different spin configurations so I set MAGMOM differently for each case.
(the unit cell has 20 atoms, La 4, Mn 4, O 12)
A- : 4*0 +4 +4 -4 -4 12*0
C- : 4*0 +4 -4 +4 -4 12*0
G- : 4*0 -4 +4 +4 -4 12 *0
Unlike the other two, C-type shows odd results.
It takes too much time to converge and its DOSCAR has huge discrepancies between spin-up and down, which are supposed to be identical.
I'm wondering if I did something wrong to set MAGMOM for C-type.
Following is my INCAR:
SYSTEM = LaMnO3
Starting parameters for this run:
NWRITE = 2 write-flag
ISTART = 0 job : 0-new, 1-cont, 2-samecut
ICHARG = 2 charge: 0-wave, 1-file, 2-atom, >10-const
ISPIN = 2
MAGMOM = 4*0 +3.5 +3.5 -3.5 -3.5 12*0
INIWAV = 1 electr: 0-lowe 1-rand 2-diag
Electronic Relaxation:
ENCUT = 500 electronvolot
PREC = normal normal | accurate
ADDGRID = .T.
NELMDL = -5 number of delayed ELM steps
NELM = 100 number of ELM steps
LREAL = .FALSE.
ALGO = Normal
NSIM = 4
LCHARG = .T.
LWAVE = .F.
LVTOT = .F.
Ionic Relaxation:
NSW = 1000 max number of geometry steps
IBRION = 1
EDIFFG = -0.02 force (eV/A)
ISIF = 3
ISYM = 1 (1-use symmetry, 0-no symmetry)
POTIM = 0.2 initial time step for geo-opt
SMASS = -1
DOS related values:
ISMEAR = 0 (-1-Fermi, 1-Methfessel/Paxton)
SIGMA = 0.05 broadening in eV
LORBIT = 11
NPAR = 8
NBLOCK = 1
KBLOCK = 1
<span class='smallblacktext'>[ Edited ]</span>
As to Mn in orthorhombic LaMnO3, there are 3 types of antimagnetism possible to exist : A-, C-, G- which have different spin configurations so I set MAGMOM differently for each case.
(the unit cell has 20 atoms, La 4, Mn 4, O 12)
A- : 4*0 +4 +4 -4 -4 12*0
C- : 4*0 +4 -4 +4 -4 12*0
G- : 4*0 -4 +4 +4 -4 12 *0
Unlike the other two, C-type shows odd results.
It takes too much time to converge and its DOSCAR has huge discrepancies between spin-up and down, which are supposed to be identical.
I'm wondering if I did something wrong to set MAGMOM for C-type.
Following is my INCAR:
SYSTEM = LaMnO3
Starting parameters for this run:
NWRITE = 2 write-flag
ISTART = 0 job : 0-new, 1-cont, 2-samecut
ICHARG = 2 charge: 0-wave, 1-file, 2-atom, >10-const
ISPIN = 2
MAGMOM = 4*0 +3.5 +3.5 -3.5 -3.5 12*0
INIWAV = 1 electr: 0-lowe 1-rand 2-diag
Electronic Relaxation:
ENCUT = 500 electronvolot
PREC = normal normal | accurate
ADDGRID = .T.
NELMDL = -5 number of delayed ELM steps
NELM = 100 number of ELM steps
LREAL = .FALSE.
ALGO = Normal
NSIM = 4
LCHARG = .T.
LWAVE = .F.
LVTOT = .F.
Ionic Relaxation:
NSW = 1000 max number of geometry steps
IBRION = 1
EDIFFG = -0.02 force (eV/A)
ISIF = 3
ISYM = 1 (1-use symmetry, 0-no symmetry)
POTIM = 0.2 initial time step for geo-opt
SMASS = -1
DOS related values:
ISMEAR = 0 (-1-Fermi, 1-Methfessel/Paxton)
SIGMA = 0.05 broadening in eV
LORBIT = 11
NPAR = 8
NBLOCK = 1
KBLOCK = 1
<span class='smallblacktext'>[ Edited ]</span>