[molpro-user] Strange results FCI for scandium atom

[Lorenzo Lodi]

Consider the attached input for three electronic states of the scandium
atom (runs in ~5 seconds).
The CASSCF energies come out with the correct degeneracies and with
quite reasonable values.
I then tried frozen-core FCI using the CASSCF orbitals and found some
rather strange results.
For example, I get for the energies
 !FCI STATE 1.6 Energy               -759.774071038492
 !FCI STATE 2.6 Energy               -759.715754355764
 !FCI STATE 3.6 Energy               -759.715754350740
 !FCI STATE 1.1 Energy               -759.715754355736

The first three energies look correct fully reasonable (ground 2D term
and two degenerate component of 2F term); however the fourth energy,
which should be the 4F term, comes out exactly the same as the 2F state,
as though even if FCI says `Spin quantum number:          1.5' it
actually used 0.5.
Another problem is that, in the first FCI block, if I specify a
different symmetry (1 or 4) I get different results, which I don't think
should be the case.

Any thoughts?

Lorenzo
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***, Calculation for Sc atom  --- Input for MOLPRO 2010.1
MEMORY, 250.00, M

basis={default, cc-pVDZ}
geometry={Sc}

! state averaged for ground 2D, 4F and 2F terms
{CASSCF; OCC, 6,3,3,1,3,1,1,0; CLOSED,3,2,2,0,2,0,0,0; FROZEN,0,0,0,0,0,0,0,0

! 4F term
WF,elec=21,sym=1,spin=3;
WF,elec=21,sym=4,spin=3; STATE,2;
WF,elec=21,sym=6,spin=3; STATE,2;
WF,elec=21,sym=7,spin=3; STATE,2;

! 2D term + 2F
WF,elec=21,sym=1,spin=1;state,3
WF,elec=21,sym=4,spin=1;state,3
WF,elec=21,sym=6,spin=1;state,3
WF,elec=21,sym=7,spin=1;state,3
 TRAN , DM, LX, LY,LZ;
 TRAN2, LXY, LXZ, LYZ, LXX,LYY,LZZ; ORBPRINT, 20
}

{FCI; WF,elec=21,sym=6,spin=1;state,3 CORE,3,2,2,0,2,0,0,0;}
{FCI; WF,elec=21,sym=1,spin=3;state,1; CORE,3,2,2,0,2,0,0,0;}