Table 4.

Molecular Vertical Excitation Energies (eV)^a

term	reference		pp	pp-SCF	SF	SF-SCF
BH
3Π		1.27	1.66	1.61	0.77	1.03
1Π	2.85		3.18	3.52	3.17	2.95
CH+
3Π	1.15		1.72	1.59	0.54	0.87
1Π	3.07		3.60	3.91	3.21	3.09
CO
3Π	6.32		5.63	6.47	5.42	6.17
1Π	8.51		7.84	9.29	8.98	9.23
N2
${}^3{\text{Σ}}_{\text{u}}^{+}$	7.75		8.32	9.03	7.96	7.51
1Πg	9.31		9.81	10.52	9.72	9.51
ethylene
3B1u	4.5		3.94	4.48	—	—
1B1u	7.8		6.28	8.69	—	—
MADb	—		0.63	0.66	0.44	0.24

^aThe aug-cc-pVDZ basis set has been used for the calculations of ethylene excitation energies. For other molecules, the aug-cc-pVTZ basis set has been used. Reference values: BH and CH⁺: computed values using CR-EOM-CCSD(T).⁴³ CO and N₂: experimental values from Ref 45. Ethylene: computed values from Ref 46.

^bMean absolute deviations from reference values.