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alex
yakovenko.alexander@gmail.com

>   As to JORDER, the thing one must remember is that if one moves all
>active orbitals to the beginning of the orbital list using JORDER
>instructions, one cannot avoid moving some occupied inactive orbitals
>beyond the limits of the initial list of inactive + active orbitals.
>This is because there are some "unoccupied" active MOs at the
>beginning of the list. The best one can do in this situation is to
>move these "extra" orbitals to the very beginning of the list of
>virtual orbitals.

>   This means that at the initial MCSCF iteration one now need to use
>the extended active space to include extra orbitals and to set MAXIT
>to 1, presumably with FOCAS converger turned on. One can reduce the
>maximum possible level of excitation though.

>   After completion of the initial MCSCF iteration, the natural
>orbitals will be computed and punched. Note, as a result of orbital
>manipulations there will be some natural orbitals having population
>very close to zero. One now need to restore the initial active space
>in $det or $drt as well as exclude these extra orbitals from the
>list of active orbitals by picking up NOs from the punch file and
>reading them in using proper $guess IORDER reordering instructions.

>Hope this helps.

>Kind regards,
>Alex Granovsky
>
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