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Pasquale Morvillo
pasquale.morvillo@portici.enea.it

http://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C34df668afbHW-6895-1374+00.htm

I got a different behavior running this job with Firefly 7.1.C (as the corresponding output found in that archive) and 7.1.G.

1. Using Firefly 7.1.G, the first gradient of the geometry search is to high and the job stop (MAXIMUM GRADIENT 29.22...).
2. Setting NOZERO=0 in $moorth, the job runs but the final energy (after geometry optimization) is higher than the one obtained in the corresponding output found in the archive and there are negative frequencies.
3. Setting ENGTOL=1.0d-11, the final energy (after geometry optimization) is equal to the one obtained in the corresponding output found in the archive; no negative frequencies were found (but they are slightly different from the output of the archive).

Can you comment the above findings?

Many thanks.

Regards

pasquale