Error EDDDAV: Call to ZHEGV failed (molecule adsorbed on M(111) surface)

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Agalya
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Error EDDDAV: Call to ZHEGV failed (molecule adsorbed on M(111) surface)

#1 Post by Agalya » Thu Sep 11, 2008 5:11 pm

Hello,

I am performing optimization of a M(111) with aromatic molecule adsorbed on the surface.

I am getting a error " Error EDDDAV: Call to ZHEGV failed


My INCAR file is
System = M(111) 4 atomic layers


ISTART=1
ICHARG=1

NPAR = 6

LPLANE = .TRUE.

ENMAX=400

LREAL = auto

!ROPT = 2e-4 2e-4

PREC = High

ALGO =Normal

NSIM =1

NGX = 86
NGY = 86
NGZ = 118

IDIPOL =3


!NBANDS = 1630
!NELM = 100
EDIFF=1e-5

ISMEAR=1
SIGMA=0.1

ISPIN=1
!MAGMOM=2 2 2 2 2 2 2 2
!ISIF = 2


NSW=100
IBRION = 2
!IPOTIM = 0.4
EDIFFG=-0.05
!NFREE = 10

LWAVE=.TRUE.

LCHARG=.TRUE.



The OUTCAR file says Warning: The distance between some ions is very small

But I checked the model. The smallest distances shown in the OUTCAR is realted to C-H and C-C bonds, which are supposed to be small. I did not find any other smallest distances.

Thanks,
Agalya
Last edited by Agalya on Thu Sep 11, 2008 5:11 pm, edited 1 time in total.

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Error EDDDAV: Call to ZHEGV failed (molecule adsorbed on M(111) surface)

#2 Post by admin » Fri Sep 12, 2008 11:10 am

please again check if these distances are resonable ("small" is somewhat qualitative) or if by error 2 atoms are on the same lattice site. Compare to experimental molecular CC and CH bond lengths (usually if the distances are comparable to experiment, this warning is not written) .
The error you report is typical for unreasonable charge densities, caused by errors in the input geometry.
Last edited by admin on Fri Sep 12, 2008 11:10 am, edited 1 time in total.

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