. 2016 Mar 10;144(10):104304. doi: 10.1063/1.4942019

TABLE VIII.

Convergence of correlation increments for the energy of the 1¹A₁ state, in mh.

Geometry		ΔE(1, 2)	ΔE(3)	ΔE(4)^a	ΔE_Corr^a^,^b	Uncertainty
OM	CAS(2,2)	−682.43	−53.26	−79.32	−815.00	±0.08
	CAS(2,2)*	−449.79	−39.65	−36.17	−525.62	±0.18
	CAS(6,4)*	−363.31	−28.36	−18.17	−409.83	±0.04
	CAS(12,7)*a	−303.43	−16.28	−10.12	−329.83	±0.02
	CAS(12,7)*b	−365.19	−26.90	−15.45	−407.54	±0.06
TS	CAS(2,2)	−662.26	−52.56	−87.59	−802.41	±0.04
	CAS(2,2)*	−436.18	−39.11	−43.64 (−44.03)	−518.93 (−519.32)	±0.42
	CAS(6,4)*	−352.25	−18.15	−23.59	−394.00	±0.15
	CAS(12,7)*a	−289.63	−9.97	−11.26	−310.86	±0.05
	CAS(12,7)*b	−352.36	−18.86	−21.62	−392.84	±0.44
XM	CAS(2,2)	−662.28	−52.68	−88.35	−803.31	±0.58
	CAS(2,2)*	−436.20	−39.26	−44.03	−519.50	±0.49
	CAS(6,4)*	−352.08	−18.16	−24.09	−394.33	±0.04
	CAS(12,7)*a	−289.68	−9.97	−11.27	−310.92	±0.05
	CAS(12,7)*b	−352.19	−19.45	−20.79	−392.43	±0.23
CI	CAS(2,2)	−665.44	−57.91	−94.39	−817.73	±0.36
	CAS(2,2)*	−443.60	−44.90	−48.95 (−49.36)	−537.45 (−537.87)	±0.79
	CAS(6,4)*	−358.96	−18.97	−25.63	−403.55	±0.17
	CAS(12,7)*a	−288.63	−9.84	−11.65	−310.12	±0.02
	CAS(12,7)*b	−359.13	−20.24	−25.22	−404.60	±0.82
RM	CAS(2,2)	−652.96	−41.05	−77.17	−771.18	±0.42
	CAS(2,2)*	−420.66	−27.58	−34.01	−482.25	±0.02
	CAS(6,4)*	−385.80	−24.83	−23.26	−433.89	±0.05
	CAS(12,7)*a	−318.10	−14.44	−12.19	−344.74	±0.02
	CAS(12,7)*b	−384.84	−25.12	−21.59	−431.54	±0.11

^{^a}

The values without parentheses were obtained using the CEEIS extrapolation for the CISDTQ increment ΔE(4). The values in parentheses for the CAS(2,2)* case at the TS and CI geometries were obtained by exact calculation of ΔE(4).

^{^b}

Total correlation energies (up to SDTQ) relative to the respective reference states.