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** Re: Some Questions on CI (GUGA) **
Thomas Pijper

thomaspijper@hotmail.com

Dear PeterP,To the best of my knowledge, it is not possible to obtain transition dipole moments with a RUNTYP=ENERGY CI run. Instead, a RUNTYP=TRANSITN run should be used. The manual has an example of how to obtain transition dipole moments from an SA-MCSCF run (linked below, see the transitn.inp file). This example should help you further in understanding the necessary input for a RUNTYP=TRANSITN run.

http://classic.chem.msu.su/gran/gamess/forum/attach/transitn.zip

I myself have little experience with these types of calculations, so I am unfortunately not able to provide much more information. If you have additional questions, please post them here and someone else will be able to help you further.

Regarding your other questions:

- With the GUGA and ALDET codes (CI and MCSCF), the first root is indeed the ground state. This is different from the TDHF/TDDFT/CIS codes, where the first root is the first excited state.

- It is not possible to use a KS-DFT reference for a CI calculation. I'm not sure if it would make any sense too. Maybe someone else has some thoughts on this.

Kind regards,

Thom

On Sat Oct 31 '15 1:34am, PeterP wrote

--------------------------------------

>Dear all,

>I am currently working on some CI calculations (CISD) with GUGA on small organic molecules (eg. benzene). I would like to know how to get transiton dipole moments from an already performed calculation with (for example) the following input for Nitrobenzene (C2v):

>

> $CONTRL SCFTYP=RHF RUNTYP=ENERGY MAXIT=30 MULT=1 MOLPLT=.TRUE. $END

> $CONTRL PLTORB=.TRUE. CITYP=GUGA INTTYP=HONDO ICUT=11 MAXIT=40 $END

> $BASIS GBASIS=N31 NGAUSS=6 NPFUNC=1 NDFUNC=1 $END

> $GUGDIA NSTATE=3 $END

> $CIDRT GROUP=C2V ISTSYM=0 NFZC=9 NDOC=23 NVAL=128 IEXCIT=2 $END

> $GUESS GUESS=HUCKEL $END

> $SCF DIRSCF=.TRUE. DIIS=.T. $END

>

>The Firefly Manual tells to use the $TRANST Keyword. But what exactly do I have to specify ?

>And just for better understanding: NSTATE ist the number of eigenvalues of the CI-Matrix and the first root corresponds to the ground state, right ?

>And a last question: The programm uses a HF reference. Is it possible to use a DFT wavefunction - Would that make sense anyway ?

>

>

>Thank you,

>PeterP

>

Sat Oct 31 '15 11:06am

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