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Re^2: MCSCF convergence problems

Andrey
andrei_ipatov@mail.ru


Dear Alex.

Thank you for your reply.

>First of all, the basis sets you are using are of spherical type.
>This means you need to add d5=.t. option to your input files.
>This will greatly reduce the degree of linear dependence of
>these basis sets.

Yes, I've suspected that there is some linear dependence,
because in the calculations with aug-cc-pVTZ basis the
final results sometimes revealed the dependence on the initial
guess. But this effect did not appeare with aug-cc-pVDZ
basis, i.e. in my case the addition of the f- states changes the
situation.

$CONTRL SCFTYP=MCSCF RUNTYP=ENERGY d5=.t. inttyp=hondo $END

Yes, thanks, I tried this. It works well with aug-cc-PVDZ and
I see the small, but visible effect, when I change
the option

$D5 d5=.t. $END to $D5 d5=.f. $END, and the latter one

gives a bit lower energies, but the degeneracy of the
states with nonzero angular momentim projection is practically
perfect in both cases.

On the contrary, with the aug-cc-pVTZ basis, that
has an extra f-orbitals with respect to the aug-cc-pVDZ one,
the use of the $contrl dt=.t. $end option
does not restore the degeneracy with any
of the combinations of
$D5 d5=.t./.f. f7=.t./.f. $END options,
despite the results are slightly different depending
on the choice of spherical/cartesian basis functions.
So far, it looks, the problem is somehow connected with the
f-orbitals of the basis set ?




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