TABLE V.

Occupations of the ORMAS orbital subspaces in the reference space and the excitation spaces for the four CI wave functions in which the 2s orbitals are treated as correlation inactive doubly occupied orbitals.^a

Active space	Reference inactive correlation inactive	Reference inactive correlation active	Reference active correlation active	Virtual orbitals
CAS(12,9)*	1a1, 1b1, 2a1,3a1, 2b1, 4a1		5a1, 3b1, 1b2, 6a1, 1a2, 4b1, 2b2, 7a1, 5b1	8a1, 6b1, etc.
Ref.	12		12	0
Ref. + SD	12		10-12	0-2
Ref. + SDT	12		9-12	0-3
Ref. + SDTQ	12		8-12	0-4
CAS(12,7)*	1a1, 1b1, 2a1,3a1, 2b1, 4a1		5a1, 3b1, 1b2, 6a1, 1a2, 4b1, 2b2	7a1, 5b1, 8a1, 6b1, etc.
Ref.	12		12	0
Ref. + SD	12		10-12	0-2
Ref. + SDT	12		9-12	0-3
Ref. + SDTQ	12		8-12	0-4
CAS(6,4)*	1a1, 1b1, 2a1,3a1, 2b1, 4a1	5a1, 3b1, 1b2	6a1, 1a2, 4b1, 2b2	7a1, 5b1, 8a1, 6b1, etc.
Ref.	12	6	6	0
Ref. + SD	12	4-6	4-8	0-2
Ref. + SDT	12	3-6	3-8	0-3
Ref. + SDTQ	12	2-6	2-8	0-4
CAS(2,2)*	1a1, 1b1, 2a1,3a1, 2b1, 4a1	5a1, 3b1, 1b2, 6a1, 1a2	4b1, 2b2	7a1, 5b1, 8a1, 6b1, etc.
Ref.	12	10	2	0
Ref. + SD	12	8-10	0-4	0-2
Ref. + SDT	12	7-10	0-4	0-3
Ref. + SDTQ	12	6-10	0-4	0-4

^aSee Section IV B for detailed explanations.