CCSD(T) Opt stops at Step 0


Clicked A Few Times
Hello,

I'm attempting to run a CCSD(T) optimization using the CCSD module. The calculation runs for a bit and stops at Step 0. It looks like the finite difference isn't converging. Running grep on the output for "step":

''''''''''''''''''''''''''''''''''
maximum cartesian step threshold   (xmax) =   0.001800
rms cartesian step threshold (xrms) = 0.001200
maximum step size to saddle (sadstp) = 0.100000
maximum number of steps (nptopt) = 50
Finite difference step 1.00000D-02
step 1 energy -434.66969586
step -1 energy -434.66960800
step 2 energy -434.66970697
step -2 energy -434.66959920
step 3 energy -434.66967658
step -3 energy -434.66962429
step 4 energy -434.66961203
step -4 energy -434.66968062
step 5 energy -434.66973786
step -5 energy -434.66954381
step 6 energy -434.66969666
step -6 energy -434.66958712
step 7 energy -434.66969982
step -7 energy -434.66958580
step 8 energy -434.66973715
step -8 energy -434.66955906
step 9 energy -434.66970317
step -9 energy -434.66959130
step 10 energy -434.66966977
step -10 energy -434.66964813
step 11 energy -434.66974296
step -11 energy -434.66954639
step 12 energy -434.66964710
step -12 energy -434.66963193
step 13 energy -434.66974047
step -13 energy -434.66952088
step 14 energy -434.66957137
step -14 energy -434.66973638
step 15 energy -434.66967561
step -15 energy -434.66962876
step 16 energy -434.66972858
step -16 energy -434.66951749
step 17 energy -434.66969961
step -17 energy -434.66960771
step 18 energy -434.66963817
step -18 energy -434.66966783
step 19 energy -434.66967295
step -19 energy -434.66964839
step 20 energy -434.66960694
step -20 energy -434.66964127
'''''''''''''''''''''''''''''''''''''''''''

What would be causing the calculation to not move to the next optimization step?

Thanks,
Stacey

Clicked A Few Times
Figured it out....it was failing since the SCF was not converging.


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