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geometry optimization slow rms convergance

glori
biyonur@gmail.com

Dear all,

I'm trying to optimize indigo substituent with B3LYP in the level of 6-311G(d,p). To speed up the convergence I used these parameters:
\$contrl INTTYP=HONDO ICUT=12 ITOL=30 \$end
\$SCF DIRSCF=.T. FDIFF=.FALSE. DIIS=.T. SOSCF=.F. \$END
\$STATPT OptTol=0.001 NStep=200 DXMAX=1 HSSEND=.TRUE. \$END

The main problem is RMS is decreasing to 0.01 in few steps but it doesn't converge more overall for 30-40 or sometimes to 100 steps. You can check input and output file generated so far.

I will use the geometry for the TD-DFT calculations, is this high amount of optimization steps are normal for gaussian.

Best Regards,

\$BASIS GBASIS=N311 NGAUSS=6 NDFUNC=1 NPFUNC=1 \$END
\$CONTRL SCFTYP=RHF RUNTYP=OPTIMIZE DFTTYP=B3LYP \$END
\$CONTRL INTTYP=HONDO ICUT=12 ITOL=30 \$end
\$SCF DIRSCF=.T. FDIFF=.FALSE. DIIS=.T. SOSCF=.F. \$END
\$CONTRL ICHARG=0 MULT=1 \$END
\$GUESS  GUESS=HUCKEL \$END
\$STATPT OPTTOL=0.001 NSTEP=200 DXMAX=1 \$END
\$SYSTEM MWORDS=64 \$END
\$DATA
B3LYP6311Gdp/4cl-indigo
C1
O           8.0  -1.6933265654   1.9985488738   0.0191162175
N           7.0   1.1515672108   1.4611156654  -0.0152791485
N           7.0  -1.1516637814  -1.4615441975   0.0189035751
C           6.0   0.6555743628   0.1747104712  -0.0057734888
C           6.0  -0.6556445508  -0.1753332759   0.0081572385
C           6.0   2.9937410068   0.0938129764  -0.0178162802
C           6.0  -2.9928546644  -0.0934514325   0.0150398416
C           6.0   2.5368337584   1.4353498938  -0.0133785905
C           6.0  -2.5377135040  -1.4350218025   0.0194648465
C           6.0   1.8050641036  -0.7758634872  -0.0174416936
C           6.0  -1.8054624753   0.7751731085   0.0233905818
C           6.0   4.3657333469  -0.1546682094  -0.0028757248
C           6.0  -4.3653973603   0.1551732620  -0.0007833082
C           6.0   3.4215666712   2.5119077074  -0.0085215626
C           6.0  -3.4214926673  -2.5116420230   0.0124488720
C           6.0   5.2669633887   0.9059001514   0.0071901142
C           6.0  -5.2679267923  -0.9058218047  -0.0038035897
C           6.0   4.7825334541   2.2188638127  -0.0004977625
C           6.0  -4.7815495000  -2.2178348676  -0.0108195935
H           1.0   0.5483153078   2.2689827662  -0.0009794627
H           1.0  -0.5473251875  -2.2696553558   0.0063159683
CL         17.0   4.9724265949  -1.7936916508  -0.0029291126
CL         17.0  -4.9724352719   1.7941099004   0.0019063362
H           1.0   3.0660049826   3.5334489583  -0.0123518717
H           1.0  -3.0666594692  -3.5332811463   0.0160232056
H           1.0   6.3282522055   0.7069077801   0.0237671500
H           1.0  -6.3283297073  -0.7073260717  -0.0289529860
H           1.0   5.4989661034   3.0359825014   0.0089235616
H           1.0  -5.4981450758  -3.0359142804  -0.0152937969
O           8.0   1.6935540761  -1.9989382240  -0.0229895359
\$END

 This message contains the 4386 kb attachment [ log6try2.log ] output file

Sun Sep 21 '14 2:31pm