about the INCAR

Message

Jiaye Li · #1 Post by **Jiaye Li** » Sat Jan 20, 2007 2:32 am

Hi
I want to optimize the slab and its density of state, i.e.Al2O3. Is my INCAR file correct? By the way, if my calculations were broken down due to power off, how can I continue my calculations?

Thanks in advance.

Startparameter for this run:
NWRITE = 2 write-flag & timer
PREC = medium medium, high low
ISTART = 0 job : 0-new 1-cont 2-samecut
ICHARG = 2 charge: 1-file 2-atom 10-const
ISPIN = 1 spin polarized calculation?
INIWAV = 1 electr: 0-lowe 1-rand 2-diag
Electronic Relaxation 1
! ENINI = 396.0 the cutoff during the initial (steepest descent) phase for IALGO=48
NELM = 500; NELMIN= 8; NELMDL=-12 # of ELM steps
EDIFF = 0.1E-04 stopping-criterion for ELM
LREAL = A real-space projection
! LCOMPAT= F compatible to vasp.4.4
! LREAL_COMPAT= F compatible to vasp.4.5.1-3
! LMAXPAW = -100 max onsite density
! LMAXMIX = 2 max onsite mixed and CHGCAR
! ROPT = -0.00100 -0.00100
Ionic relaxation
EDIFFG = 0.1E-03 stopping-criterion for IOM
NSW = 1000 number of steps for IOM
NBLOCK = 1; KBLOCK = 1 inner block; outer block
IBRION = 2 ionic relax: 0-MD 1-quasi-New 2-CG
NFREE = 2 steps in history (QN), initial steepest desc. (CG)
ISIF = 2 stress and relaxation
! IWAVPR = 10 prediction: 0-non 1-charg 2-wave 3-comb
ISYM = 0 0-nonsym 1-usesym 2-fastsym
LCORR = T Harris-Foulkes like correction to forces

POTIM = 0.1 time-step for ionic-motion
! TEBEG = 500.0; TEEND = 500.0 temperature during run
SMASS = 2.00 Nose mass-parameter (am)
Atomic Wigner-Seitz radii
! RWIGS = -1.00 -1.00
! NELECT = 288.0000 total number of electrons
! NUPDOWN= -1.0000 fix difference up-down

DOS related values:
EMIN = 15.00; EMAX =-10.00 energy-range for DOS
ISMEAR = -5; SIGMA = 0.20 broadening in eV -4-tet -1-fermi 0-gaus

Electronic relaxation 2 (details)
IALGO = 48 algorithm
LDIAG = T sub-space diagonalisation
! IMIX = 4 mixing-type and parameters
! AMIX = 0.20; BMIX = 0.0001
! AMIX_MAG = 0.80; BMIX_MAG = 0.0001
! AMIN = 0.10
! WC = 1000; INIMIX= 1; MIXPRE= 1

Intra band minimization:
! WEIMIN = 0.0010 energy-eigenvalue tresh-hold
! EBREAK = 0.14E-06 absolut break condition
! DEPER = 0.30 relativ break condition

! TIME = 0.10 timestep for ELM

Second variation
LSECVAR= F do a second variation

Write flags
LWAVE = T write WAVECAR
LCHARG = T write CHGCAR
LVTOT = T write LOCPOT, local potential
LORBIT = 10
LELF = T write electronic localiz. function (ELF)

#2 Post by **admin** » Mon Jan 22, 2007 12:39 pm

you need not set LELF, this will just cost computing time.
SMASS need not be set for CG structure optimization.
rather use the forces as geometry convergence criterium (EDIFFG= -0.01 should be sufficiently accurate)

concerning your second question: if a job breaks, re-start from the last CONTCAR file (as new POSCAR), so the information obtained for the ionic reaxation is not lost.

Jiaye Li · #3 Post by **Jiaye Li** » Fri Jan 26, 2007 6:12 am

Thanks for your suggestion
What is the differenc between EDIFFG for energy criteriun and for force criteriun ?

If I need to re-start the job, should I change ISTART to 1?

Jiaye Li · #4 Post by **Jiaye Li** » Fri Jan 26, 2007 6:13 am

<span class='smallblacktext'>[ Edited Fri Jan 26 2007, 07:15AM ]</span>

#5 Post by **admin** » Mon Jan 29, 2007 2:23 pm

please have a look in the online handbook concerning EDIFFG.
if you want to use the WAVECAR file of the previous run (please check if it is not empty), copy CONTCAR to POSCAR and re-start with ISTART=1. If WAVECAR is not taken to continue, ISTART need not be set explicitely

Jiaye Li · #6 Post by **Jiaye Li** » Thu Feb 01, 2007 7:04 am

Thanks

Alenushka · #7 Post by **Alenushka** » Tue Feb 06, 2007 1:43 pm

http://cms.mpi.univie.ac.at/vasp/vasp/node98.html