PC GAMESS/Firefly-related discussion club

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Alex Granovsky
gran@classic.chem.msu.su

>My input file looks like as
> $CONTRL SCFTYP=RHF ICHARG=0 MULT=1 MAXIT=200 $END
> $CONTRL EXETYP=check RUNTYP=transitn COORD=cart CITYP=GUGA $END
> $CIDRT1 GROUP=C1 IEXCIT=1 NFZC=307 NDOC=3 NVAL=630 $END
> $GUGDIA ITERMX=500 $END
> $SYSTEM TIMLIM=100000 MEMORY=90000000 $END
> $BASIS  GBASIS=N21 NGAUSS=3 $END
> $TRANST IROOTS(1)=1,4 $END

GUGA CI code, as well as the associated integral transformation,
is not very suitable for large-scale CIS calculations, nor it was
designed with them in mind.

Use CITYP=CIS with RUNTYP=ENERGY.
The AO-driven CIS code in Firefly is documented here:

http://classic.chem.msu.su/gran/gamess/cis.html

You'll get printout of the transition dipoles between all the
states of interest, and this is basically the same information
you would get performing RUNTYP=transitn run.

An additional advantage is that there is no need to freeze
all occupied MOs but the last three, as suggested in your input
(sure if you do like you still can do this).

Regards,
Alex