Table 2:

List of compounds, experimental Δ_fH^○, and deviations between the experiment and the calculations^a

		experimentalb			$({\Delta }_{\text{f}}{H}^{\circ },\text{exp}-{\Delta }_{\text{f}}{H}^{\circ },\text{calc})$ c
name	formula	${\Delta }_{\text{f}}{H}^{\circ }$	U	Ref.	S	M	L	M-DFT	S+	G4	G4-E
methane	CH4	−74.53	0.06	39	0.6	−1.7	−1.7	−1.6	−1.7	0.1	1.7
ethane	C2H6	−83.78	0.15	39	1.6	−0.3	−0.3	−0.2	−0.3	−0.6	1.1
propane	C3H8	−104.6	0.2	39	1.8	0.2	0.2	0.3	0.2	−1.2	0.8
butane	C4H10	−125.8	0.3	39	1.8	0.4	0.4	0.5	0.3	−1.5	0.8
isobutane	C4H10	−135.1	0.5	49–51	0.2	−1.5	−1.5	−1.4	−1.6	−2.5	−0.2
neopentane	C5H12	−168.0	0.8	46	1.0	−1.6	−1.6	−1.4	−1.6	−0.7	1.7
cyclohexane	C6H12	−123.3	0.8	46	1.1	0.2	0.2	0.3	0.1	−3.7	−1.9
ethylene	C2H4	52.53	0.14	39	2.3	0.3	0.3	0.1	0.7	0.2	1.1
propene	C3H6	20.3	0.3	39	1.8	0.3	0.3	0.2	0.6	−0.4	0.9
(E)-2-butene	C4H8	−11.2	0.5	39	0.8	−0.6	−0.6	−0.7	−0.5	−1.6	0.1
(z)-2-butene	C4H8	−7.3	0.5	39	−1.1	−1.8	−1.9	−1.9	−1.7	−3.2	−1.7
cyclohexene	C6H10	−5.0	1.0	52–54	0.8	0.4	0.4	0.4	0.5	−3.5	−2.5
norbornene	C7H10	81.9	1.7	55–57	3.7	2.7	2.6	3.0	2.8	1.0	1.7
1,3-butadiene	C4H6	110.0	1.0	46	−0.1	−1.7	−1.7	−1.9	−1.1	−1.8	−0.8
ethyne	C2H2	228.32	0.14	39	3.1	0.7	0.8	0.5	1.0	−0.5	−0.2
propyne	C3H4	185.1	0.5	58–60	2.5	0.0	0.2	−0.2	0.2	−0.7	−0.5
1-butyne	C4H6	165.4	0.9	39	1.4	−0.8	−0.7	−0.9	−0.7	−2.2	−1.7
benzene	C6H6	82.9	0.9	47	0.1	0.9	1.0	0.9	1.1	−1.8	−2.0
styrene	C8H8	148.0	1.4	46	−2.0	−1.4	−1.4	−1.7	−1.3	−1.1	−1.4
naphthalene	C10H8	150.6	1.5	47	−0.6	1.0	1.0	1.2	0.6	3.6	2.0
biphenyl	C12H10	180.2	1.8	61–68	−0.8	0.8	0.9	0.8	0.6	3.2	1.6
water	H2O	−241.83	0.04	48	−13.5	−0.4	−0.3	−0.5	−0.6	−1.8	−1.2
carbon dioxide	CO2	−393.51	0.13	48	9.6	1.5	1.5	1.9	2.0	3.6	1.6
methanol	CH 4 O	−200.7	0.2	39	−3.8	1.0	1.0	0.9	0.9	0.2	0.9
ethanol	C2H6O	−234.6	0.2	39	−3.8	0.9	1.0	0.9	0.8	−0.7	0.2
2-propanol	C3H8O	−272.8	0.4	39	−3.5	0.8	0.8	0.8	0.6	−0.9	0.3
2-methylpropan-2-ol	C4H10O	−312.5	0.8	46	−3.5	−0.2	−0.2	−0.1	−0.4	−0.2	1.2
phenol	C6H6O	−95.7	1.1	69–74	−7.8	−2.8	−2.7	−2.8	−2.8	−4.9	−5.6
1-naphthol	C10H8O	−27.5	1.7	75–77	−7.2	−1.7	−1.7	−1.4	−2.2	2.0	0.1
dimethyl ether	C2H6O	−184.0	0.4	39	2.6	0.7	0.7	0.5	0.9	0.7	1.6
anisole	C7H8O	−69.9	1.0	78–82	0.3	−0.3	−0.4	−0.6	−0.2	0.0	−0.7
methanal	CH 2 O	−109.16	0.11	39	6.5	2.1	2.1	1.9	2.8	2.7	2.3
ethanal	C2H4O	−165.5	0.3	39	4.6	0.8	0.8	0.8	1.2	0.6	0.6
propanone	C3H6O	−216.1	0.4	39	3.5	0.2	0.2	0.3	0.4	−0.3	0.0
formic acid	CH2O2	−378.5	0.2	39	1.9	1.3	1.3	1.2	1.2	0.2	−0.6
acetic acid	C2H4O2	−432.8	0.6	39	−1.2	−1.4	−1.4	−1.4	−1.8	−2.8	−3.4
benzoic acid	C7H6O2	−294.1	1.0	83, d	0.8	1.5	1.6	1.5	0.9	1.2	−0.9
ammonia	H3N	−45.56	0.03	39	−7.2	−0.2	−0.1	−0.2	−0.5	−2.8	−0.6
acetonitrile	C2H3N	74.0	0.3	46	11.0	2.2	2.4	2.4	2.8	1.2	2.0
urea	CH4N2O	−237.8	0.5	84–92	−5.5	−2.0	−2.0	−2.1	−2.8	−5.6	−3.6
piperidine	C5H11N	−47.3	0.8	93–97	2.2	2.6	2.6	2.8	2.7	−0.8	1.5
pyridine	C5H5N	140.4	0.7	46	5.5	2.0	2.0	2.0	2.6	0.6	0.8
aniline	C6H7N	87.1	1.2	98–102	−3.7	0.6	0.7	0.4	0.6	−1.5	−0.5
nitrobenzene	C6H5NO2	66.0	1.1	102–104,e	5.6	−1.7	−1.8	−1.5	−0.4	8.5	6.6
benzamide	C7H7NO	−99.8	1.0	98,99,105–109	−2.6	−1.7	−1.7	−1.7	−2.2	−2.1	−2.5
standard deviation					4.6	1.4	1.4	1.4	1.5	2.5	2.0

a energy units are kJ·mol⁻¹;

b U represents expanded uncertainty (0.95 level of confidence);

c S, M, L, M-DFT, and S+ refer to “small”, “medum”, “large”, “medium-DFT”, and “small+” schemes, respectively (see Table 1);

d enthalpy of sublimation was evaluated using the NIST ThermoData Engine 10.1 software¹¹⁰ with full list of literature sources available;¹¹¹

e the enthalpy of combustion reported in Ref. 103 was corrected to −(3086.7 ± 0.7) kJ·mol⁻¹ because the term for adjustment to the standard pressure (estimated to be 6 J·g⁻¹) had an incorrect sign; the resulting liquid-phase standard enthalpy of formation is 11.1 ± 1.0 kJ·mol⁻¹