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Extracting energy from Gaussian output

I tried to read energies from Gaussian output-file (*.log for g09 or g16) with Avogadro (v. 1.2.0). I realized that calculated with DFT energies (HF) in the file are different than that showed by software (View - Properties - Molecule Properties …). Unfortunately I could not find any information about details of the procedure used to extract the energy from *.log file.

Could anyone explain me in detail the procedure of extracting energy from Gaussian output

Can you give me an example? Avogadro always shows energies in kJ/mol so there’s a conversion from Hartree. But it should read the total energy from a calculation. Otherwise, an example file or screenshot (or both) would be very helpful.

Screenshot: comparison of energies calculated with g16 (DFT - CAM-B3LYP) for different basis sets:

  • “from Avogadro”: read out form *.log files with Avogadro (View - Properties - Molecule Properties …);
  • “HF from *.log”: read fro *.log file and converted to kJ / mol wit energy converter (http://www.colby.edu/chemistry/PChem/Hartree.html).