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** geometry optimization of the first excited state of the CH2NH2 free radical **
Patrick SK Pang

pangsiukwong@gmail.com

Dear all,Could you tell me whether the below iput is OK or not? I want to perform the geometry optimization of the first excited state of the CH2NH2 free radical.

I have many molecules calculated by CIS before. Now, I need to calculate free radicals so GUGA is employed since CIS cannot handle free radical. Can the results from the below input be "fairly" compared with the CIS results? I hope the comparison between the properties of molecules calculated using CIS and those using GUGA does not affected by different algorithms.

$CONTRL RUNTYP=Optimize $END

$CONTRL SCFTYP=ROHF $END

$CONTRL ICHARG=0 MULT=2 $END

$CONTRL NZVAR=12 $END

$CONTRL CITYP=GUGA $END

$CIDRT GROUP=C1 IEXCIT=1 NFZC=2 NDOC=8 $END

$GUGDIA NSTATE=1 $END

$GUGDM IROOT=1 $END

$ZMAT DLC=.T. AUTO=.T. $END

$BASIS GBASIS=N31 NGAUSS=6 $END

$BASIS NDFUNC=1 NPFUNC=1 $END

$BASIS DIFFSP=.TRUE. DIFFS=.TRUE. $END

$SYSTEM TIMLIM=10000 MWORDS=100 $END

$P2P P2P=.T. DLB=.T. $END

$STATPT NSTEP=200 METHOD=GDIIS $END

$DATA

Molecule specification

C1

H �1.000000 1.064677 -0.821779 -0.922526

H �1.000000 1.588606 1.320499 -0.500262

C �6.000000 0.700677 -0.298779 -0.037526

N �7.000000 1.205677 1.059221 -0.037526

H �1.000000 0.875677 1.540221 0.786474

H �1.000000 1.052677 -0.804779 0.861474

$END

Thanks!

Regards,

Patrick

Tue Apr 16 '13 7:02pm

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