Recommendation

You will normally only need to enter eht. For the EHT-guess, define will ask for some specifications, and you should always choose the default, i.e. just . Of importance is only the molecular charge, specified as 0 (neutral, default), 1 or -1 etc.

Based on the EHT orbital energies define proposes an occupation. If you accept you are done, if not you get the ``occupation number assignment menu'' explained in 4.3.2.