. 2024 Dec 13;20(24):10886–10898. doi: 10.1021/acs.jctc.4c01240

Table 1. Summary Statistics within the G2 Test Set^a of CMA-0A Residuals for CCSD(T)/cc-pVTZ Harmonic Vibrational Frequencies (ϵ, cm^–1) and ZPVEs (Δ, cm^–1) as Compared to the Corresponding Pure Level B Errors.

Level B		MAE ϵ	mean ϵ	ϵ_max^b	σ_ϵ	ϵ_MAX^c	MAE Δ	mean Δ	σ_Δ
MP2/cc-pVTZ^d	pure	9.44	5.62	28.2	13.68	145	40.6	38.3	39.1
	CMA	0.11	0.02	0.54	0.49	9.3	0.12	0.12	0.24
df-MP2/cc-pVTZ^d^,^e	pure	9.00	5.19	27.2	12.55	146	37.9	35.6	32.0
	CMA	0.11	0.02	0.53	0.49	9.3	0.11	0.11	0.24
HF/cc-pVTZ	pure	56.92	54.95	94.7	34.41	251	374.4	371.5	294.7
	CMA	1.09	0.14	5.18	4.93	86.3	0.95	0.95	1.56
B3LYP/6-31G(2df,p)	pure	8.82	4.66	23.1	10.86	69	36.0	31.5	33.3
	CMA	0.16	0.04	0.59	0.36	3.4	0.27	0.27	0.32
CCSD(T)/cc-pVDZ	pure	47.54	47.12	120.0	54.46	173	319.0	318.6	244.6
	CMA	0.22	0.04	0.74	0.45	4.0	0.27	0.27	0.29
CCSD/cc-pVDZ	pure	54.34	54.05	128.2	53.55	165	365.5	365.5	267.4
	CMA	0.23	0.04	0.77	0.46	3.6	0.29	0.29	0.29
MP2/cc-pVDZ^d	pure	52.52	52.15	139.4	60.38	213	355.3	355.3	253.4
	CMA	0.32	0.06	1.18	0.83	11.6	0.38	0.38	0.41
HF/cc-pVDZ	pure	85.11	83.88	132.8	47.55	247	567.8	567.1	440.4
	CMA	0.72	0.12	3.45	3.02	58.4	0.81	0.81	1.17

The instructive case of pyridine is omitted from these statistics and dissected in a later section, leaving 1501 frequencies in the data set.

Average maximum absolute ϵ per molecule.

Maximum absolute ϵ over the entire data set.

Excluding ω₃(O₃), for which MP2 is a catastrophic failure.⁴⁹

Excluding ω₃(NO₂), for which df-MP2 in Psi4 does not run successfully.

Table 1. Summary Statistics within the G2 Test Seta of CMA-0A Residuals for CCSD(T)/cc-pVTZ Harmonic Vibrational Frequencies (ϵ, cm–1) and ZPVEs (Δ, cm–1) as Compared to the Corresponding Pure Level B Errors.