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eburresi
emiliano.burresi@gmail.com

I'm trying to perform DFT-BLYP calculation on CdS nanocluster with 48 Cd atoms and 48 S atoms, using 3-21g and sto-3g basis set,
but I'm finding some convergence problems during SCF optimization. I tried to use combo,
building an intial guess from  optimized molecular orbitals of sulphur and cadmium fragments separately but in my case didn’t help a lot.
The atom coordinates are from CPMD ab initio molecular dinamics simulations.
I hope that someone can help me.

$CONTRL SCFTYP=RHF  RUNTYP=ENERGY NOSYM=1 COORD=UNIQUE UNITS=ANGS
ICHARG=0  MAXIT=2000 DFTTYP=BLYP  $END
$SYSTEM TIMLIM=600 MEMORY=70000000 $END
$SCF    DIRSCF=.True. DIIS=.T. FDIFF=.F.
         SHIFT=.T. SOSCF=.F.  $END
$GUESS  GUESS=HUCKEL $END
$BASIS  GBASIS=N21  NGAUSS=3  $END
$DATA
CdS Cluster 96 Temperature 340K
C1


Thank you in advance
 Emiliano