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MC-SCF problem

Michal P Krompiec
michal.krompiec@gmail.com

Hello, I am trying to converge a 'difficult' MC-SCF case (first step in MR-MPT2). Recently I got an error like this:
****** DAVIDSON METHOD NOT CONVERGED AFTER  50 ITERATIONS ******
Is there any way to increase the number of davidson iterations?
The calculation is GUGA CASSCF(12,10). CASSCF(8,7) converged without any problems. I know that the active space is "theoretically" far too small, and the basis set is too small too (I'm trying TZV in paralell). The goal of these calculations is to get a reference result to compare with TD-DFT.

This is the beginning of my input file:

\$CONTRL SCFTYP=MCSCF RUNTYP=ENERGY MAXIT=100
COORD=UNIQUE D5=.TRUE. UNITS=ANGS  NZVAR=2
mplevl=2 \$END
\$SYSTEM MWORDS=50 TIMLIM=60000  MXIOB(1)=10240,1024 fastf=.f. \$END
\$INTGRL packao=.t. \$END
\$BASIS GBASIS=N31 NGAUSS=6 NDFUNC=1 \$END
\$MCSCF CISTEP=GUGA numfo=20 fullnr=.f.
\$DRT GROUP=C1 FORS=.t. NMCC=66 NDOC=6 NVAL=4 \$END
\$gugdia nstate=4 \$end
\$XMCQDPT EDSHFT=0.2 NSTATE=3
\$END
\$TRANS DIRTRF=.true. \$END
\$MCQFIT \$END
\$SMP NP=60 SMPPAR=.t. \$END
\$P2P P2P=.t. dlb=.t. \$END

Any help will be appreciated.
Best regards,
Michal

Mon Jun 2 '14 2:21pm