The ABINIT Users Mailing List ( CLOSED )

["Nichols A. Romero" <nromero@uiuc.edu>]

Hi,

I've been having some difficulties getting the SCF cycle to converge for
DFT-LDA calculation on some C28-derived molecules. I've done
calculations on molecules before using LCAO basis and PW basis and I
know the latter is always trickier but I've never had this much trouble.

If I have iscf=5 (default), I will eventually get the infamous
scfcge: ERROR - Potential-based CG line minimization not converged

I have tried a number of things including using occopt=3 with
tsmear=0.01 and nline=10.

The only thing that seems to work is iscf=3, but it sometimes takes over
200 SCF cycles before it convergence.

Here are some other relevant parameters, maybe someone can let me know
if I've set one of them incorrectly.
diemix 0.3
diemax 2.0
acell  3*30 (I think that I should have enough vacuum)

I can send a complete input file if necessary.

Bests,
-- 
Nichols A. Romero

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