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Dear all,

I run relaxation calcuation for 1x1x1 SrTiO3 with LDA+U.
This is my INCAR:

NWRITE = 2 ! write-flag
PREC = medium ! low medium high
ISTART = 0 ! job : 0-new, 1-cont, 2-samecut
ICHARG = 2 ! charge: 0-wave, 1-file, 2-atom, >10-const
ISPIN = 2
MAGMOM = 5*4
AMIX = 0.2
BMIX = 0.0001 ! almost zero, but 0 will crash some versions
AMIX_MAG = 0.8
BMIX_MAG = 0.0001 ! almost zero, but 0 will crash some versions

ENCUT = 500
EDIFF = 1E-04 ! energy stopping-criterion for ELM
LWAVE = .FALSE.
LCHARG = .TRUE.
LREAL = .TRUE.

IBRION = 2 ! ionic relaxation: 0-MD, 1-quasi-Newton, 2-CG, 3-Damped MD
ISIF = 2 ! relax ions & shape & volume
NSW = 200 ! max number of geometry steps
EDIFFG = -1E-3 ! stopping-criterion for geometry steps
ISYM = 2 ! 1-use symmetry, 0-no symmetry
POTIM = 0.4 ! initial time step for geo-opt

ISMEAR = -5 ! (-1-Fermi, 1-Methfessel/Paxton)
SIGMA = 0.02 ! broadening in eV

Parallelization flags:
NPAR = 1
LPLANE = .TRUE.

LDAU parameters:
LDAU = .TRUE.
LDAUTYUPE = 2
LDAUL = 2 -1
LDAUU = 8.00 0.00
LDAUJ = 1.00 0.00
LDAUPRINT = 2

and I receive the follwing error message:

Error reading item 'LDAUL' from file INCAR.
Error code was IERR= 0 Found N= 2 data items
Error reading item 'LDAUU' from file INCAR.
Error code was IERR= 0 Found N= 2 data items
Error reading item 'LDAUJ' from file INCAR.
Error code was IERR= 0 Found N= 2 data items

plase explain me!

Thanks very much!

Hello,
Firstly, you have a typo 'LDAUTYUPE=2'.
And then, you have two values after the = for LDAUL, LDAUU and LDAUJ, when apparently only one is required. (Hence the error 'Found N=2 data items)(http://cms.mpi.univie.ac.at/vasp/vasp/node146.html)

Cheers

Can't be this Tyx:
I'm using:

LDAU = .TRUE.
LDAUTYPE = 2 #Dudarev’s approach
LDAUL = 3 -1 #Ce and O
LDAUU = 7 0 #Ce and O
LDAUJ = 0 0 #Ce and O
LMAXMIX = 6 #is Ce (f element)

And got the same error (but with only one data item):

Error reading item 'LDAUL' from file INCAR.
Error code was IERR= 0 Found N= 1 data items
Error reading item 'LDAUU' from file INCAR.
Error code was IERR= 0 Found N= 1 data items
Error reading item 'LDAUJ' from file INCAR.
Error code was IERR= 0 Found N= 1 data items

VASP manual says:
NB: LDAUL, LDAUU, and LDAUJ must be specified for all atomic species!

Any help?

Which elements do you have in the POSCAR file? You say you are calculating SrTiO3, so if you have three elements there, you need three values after the LDAUL flag.

When I was work with CeO2, I set for instance:

LDAUL= 3 -1 #two numbers for two ions

But the error persist:

Error reading item 'LDAUL' from file INCAR.
Error code was IERR= 0 Found N= 1 data items

To solve it I did:

LDAUL= 3 -1 -1 #my cell had one Ce and two O; I guess it can work

It worked, but in the OUTCAR file I've found:

angular momentum for each species LDAUL = 3 -1

VASP only take the first and the second number, but I had to type three numbers in order to avoid the error. Also for LDAUU and LDAUJ (7 0 0 and 0 0 0, respectively).

Why?
I just don't know.
But it works.

I fogot something:

When I works with CuO/CeO2 I only needed to set 3 parametres: one for each kind of atom (Cu, Ce, O).

Maybe three are the minimun, although it doesn't use all.

No, three is no minimum, I once started an LDAU calculation with only one species. I set one number after the LDAUL tag and it worked.