Selected ATcT [1, 2] enthalpy of formation based on version 1.172 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.156 to include species relevant to a study of photodissociation of formamide[4].

Methylamine

Formula: CH3NH2 (g)

CAS RN: 74-89-5

ATcT ID: 74-89-5*0

SMILES: CN

InChI: InChI=1S/CH5N/c1-2/h2H2,1H3

InChIKey: BAVYZALUXZFZLV-UHFFFAOYSA-N

Hills Formula: C1H5N1

2D Image:

Aliases: CH3NH2; Methylamine; Methanamine; Monomethylamine; Aminomethane; Carbinamine; Mercurialin; Methylaminen; UN 1061; UN 1235; NH2CH3

Relative Molecular Mass: 31.05714 ± 0.00088

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
-6.45	-21.16	± 0.22	kJ/mol

3D Image of CH3NH2 (g)

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Top contributors to the provenance of Δ_fH° of CH3NH2 (g)

The 20 contributors listed below account only for 44.7% of the provenance of Δ_fH° of CH3NH2 (g).
A total of 220 contributors would be needed to account for 90% of the provenance.

Please note: The list is limited to 20 most important contributors or, if less, a number sufficient to account for 90% of the provenance. The Reference acts as a further link to the relevant references and notes for the measurement. The Measured Quantity is normaly given in the original units; in cases where we have reinterpreted the original measurement, the listed value may differ from that given by the authors. The quoted uncertainty is the a priori uncertainty used as input when constructing the initial Thermochemical Network, and corresponds either to the value proposed by the original authors or to our estimate; if an additional multiplier is given in parentheses immediately after the prior uncertainty, it corresponds to the factor by which the prior uncertainty needed to be multiplied during the ATcT analysis in order to make that particular measurement consistent with the prevailing knowledge contained in the Thermochemical Network.

Contribution (%)	TN ID	Reaction	Measured Quantity	Reference
8.1	2660.12	CH3NH2 (g) → C (g) + N (g) + 5 H (g)	Δ_rH°(0 K) = 2268.24 ± 0.74 kJ/mol	Gratzfeld 2017
3.8	2669.8	CH3NH2 (g) + H2O (g) → CH3OH (g) + NH3 (g)	Δ_rH°(0 K) = 4.07 ± 0.25 kcal/mol	Karton 2011
3.7	2668.8	CH3NH2 (g) + CH4 (g) → CH3CH3 (g) + NH3 (g)	Δ_rH°(0 K) = -8.14 ± 0.25 kcal/mol	Karton 2011
3.2	9060.2	CH3CH2NH2 (g) + NH3 (g) → 2 CH3NH2 (g)	Δ_rH°(0 K) = 54.20 ± 1.5 kJ/mol	Klippenstein 2017
2.8	2660.11	CH3NH2 (g) → C (g) + N (g) + 5 H (g)	Δ_rH°(0 K) = 542.22 ± 0.30 kcal/mol	Karton 2008, Karton 2011
2.0	5355.1	2 (CH3)2NH (l) + 15/2 O2 (g) → 4 CO2 (g) + 7 H2O (cr,l) + N2 (g)	Δ_rH°(298.15 K) = -833.42 ± 0.20 (×2.709) kcal/mol	Jaffe 1970, Cox 1970, as quoted by Cox 1970
1.9	2665.1	CH4 (g) + NH3 (g) → CH3NH2 (g) + H2 (g)	Δ_rH°(0 K) = 99.10 ± 1.5 kJ/mol	Klippenstein 2017
1.9	5356.1	(CH3)2NH (g) + NH3 (g) → 2 CH3NH2 (g)	Δ_rH°(298.15 K) = 4.68 ± 0.40 kcal/mol	Issoire 1960, as quoted by Cox 1970
1.8	2669.9	CH3NH2 (g) + H2O (g) → CH3OH (g) + NH3 (g)	Δ_rH°(0 K) = 16.30 ± 1.5 kJ/mol	Klippenstein 2017
1.8	2668.9	CH3NH2 (g) + CH4 (g) → CH3CH3 (g) + NH3 (g)	Δ_rH°(0 K) = -34.98 ± 1.5 kJ/mol	Klippenstein 2017
1.6	9060.1	CH3CH2NH2 (g) + NH3 (g) → 2 CH3NH2 (g)	Δ_rH°(0 K) = 13.03 ± 0.50 kcal/mol	Lee 2021, est unc
1.6	2686.11	CH3NH (g) → C (g) + N (g) + 4 H (g)	Δ_rH°(0 K) = 444.22 ± 0.30 kcal/mol	Karton 2008, Karton 2011
1.5	2669.7	CH3NH2 (g) + H2O (g) → CH3OH (g) + NH3 (g)	Δ_rH°(0 K) = 4.10 ± 0.4 kcal/mol	Karton 2011
1.4	2668.7	CH3NH2 (g) + CH4 (g) → CH3CH3 (g) + NH3 (g)	Δ_rH°(0 K) = -8.16 ± 0.4 kcal/mol	Karton 2011
1.3	5356.11	(CH3)2NH (g) + NH3 (g) → 2 CH3NH2 (g)	Δ_rH°(0 K) = 20.50 ± 2.0 kJ/mol	Klippenstein 2017
1.2	5356.10	(CH3)2NH (g) + NH3 (g) → 2 CH3NH2 (g)	Δ_rH°(0 K) = 4.88 ± 0.50 kcal/mol	Lee 2021, est unc
1.1	2674.11	CH2NH2 (g) → C (g) + N (g) + 4 H (g)	Δ_rH°(0 K) = 451.03 ± 0.30 kcal/mol	Karton 2008, Karton 2011
1.0	5569.5	(CH3)3N (g) + 2 NH3 (g) → 3 CH3NH2 (g)	Δ_rH°(0 K) = 12.71 ± 0.85 kcal/mol	Ruscic W1RO
1.0	2666.1	2 CH3NH2 (l) + 9/2 O2 (g) → 2 CO2 (g) + 5 H2O (cr,l) + N2 (g)	Δ_rH°(298.15 K) = -507.08 ± 0.18 (×5.301) kcal/mol	Jaffe 1970, Cox 1970, as quoted by Cox 1970
1.0	7835.5	NH2C(O)NH2 (g) + 2 CH4 (g) → CH2O (g) + 2 CH3NH2 (g)	Δ_rH°(0 K) = 55.40 ± 0.9 kcal/mol	Ruscic W1RO

Top 10 species with enthalpies of formation correlated to the Δ_fH° of CH3NH2 (g)

Please note: The correlation coefficients are obtained by renormalizing the off-diagonal elements of the covariance matrix by the corresponding variances.
The correlation coefficient is a number from -1 to 1, with 1 representing perfectly correlated species, -1 representing perfectly anti-correlated species, and 0 representing perfectly uncorrelated species.

Correlation Coefficent (%)	Species Name	Formula	Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
87.5	Methylammoniumyl	[CH3NH2]+ (g)	865.98	852.05	± 0.25	kJ/mol	31.05659 ± 0.00088	34516-31-9*0
47.6	Methylamine	CH3NH2 (l)		-45.18	± 0.44	kJ/mol	31.05714 ± 0.00088	74-89-5*500
42.2	Methylamidogen	CH3NH (g)	187.98	177.33	± 0.40	kJ/mol	30.04920 ± 0.00085	15622-51-2*0
42.1	Dimethylamine	(CH3)2NH (g)	4.63	-17.01	± 0.47	kJ/mol	45.0837 ± 0.0017	124-40-3*0
39.3	Aminomethyl	CH2NH2 (g)	159.41	149.57	± 0.35	kJ/mol	30.04920 ± 0.00085	10507-29-6*0
36.3	Ethylamine	CH3CH2NH2 (g)	-28.05	-49.82	± 0.45	kJ/mol	45.0837 ± 0.0017	75-04-7*0
35.1	Trimethylamine	(CH3)3N (g)	2.64	-26.21	± 0.79	kJ/mol	59.1103 ± 0.0025	75-50-3*0
34.1	Aminomethylium	[CH2NH2]+ (g)	763.61	751.64	± 0.53	kJ/mol	30.04865 ± 0.00085	488821-23-4*0
30.6	Trimethylamine	(CH3)3N (l)		-48.32	± 0.89	kJ/mol	59.1103 ± 0.0025	75-50-3*500
30.4	Methylamidogen anion	[CH3NH]- (g)	145.40	134.57	± 0.64	kJ/mol	30.04975 ± 0.00085	54448-39-4*0

Most Influential reactions involving CH3NH2 (g)

Please note: The list, which is based on a hat (projection) matrix analysis, is limited to no more than 20 largest influences.

Influence Coefficient	TN ID	Reaction	Measured Quantity	Reference
0.995	2661.1	CH3NH2 (g) → [CH3NH2]+ (g)	Δ_rH°(0 K) = 72930 ± 10 cm-1	Baek 2003
0.731	2667.1	CH3NH2 (l) → CH3NH2 (g)	Δ_rH°(298.15 K) = 23.85 ± 0.45 kJ/mol	Majer 1985
0.516	2694.1	CH3NH2 (g) + [NH2]- (g) → [CH3NH]- (g) + NH3 (g)	Δ_rG°(296 K) = -0.51 ± 0.20 kcal/mol	MacKay 1976, note unc2
0.407	2684.1	CH3NH2 (g) → [CH2NH2]+ (g) + H (g)	Δ_rH°(0 K) = 10.228 ± 0.008 eV	Bodi 2006
0.336	2662.6	[CH3NH2]- (g) → CH3NH2 (g)	Δ_rH°(0 K) = -0.983 ± 0.050 eV	Ruscic W1RO
0.316	2673.11	[CH3NH3]+ (g) + NH3 (g) → CH3NH2 (g) + [NH4]+ (g)	Δ_rH°(0 K) = 11.30 ± 0.40 kcal/mol	Lee 2021, est unc
0.248	2695.1	[CH3NH]- (g) + H2 (g) → H- (g) + CH3NH2 (g)	Δ_rG°(296 K) = -1.46 ± 0.29 kcal/mol	MacKay 1976, note unc2
0.231	2667.2	CH3NH2 (l) → CH3NH2 (g)	Δ_rH°(298.15 K) = 24.3 ± 0.8 kJ/mol	NBS Tables 1989
0.226	5568.1	(CH3)3N (g) + CH3NH2 (g) → 2 (CH3)2NH (g)	Δ_rH°(298.15 K) = 3.08 ± 0.40 kcal/mol	Issoire 1960, as quoted by Cox 1970
0.204	2672.9	[CH3NH3]+ (g) → CH3NH2 (g) + H+ (g)	Δ_rH°(0 K) = 213.41 ± 0.50 kcal/mol	Lee 2021, est unc
0.187	2693.3	CH3NH (g) + NH3 (g) → CH3NH2 (g) + NH2 (g)	Δ_rH°(0 K) = 8.01 ± 0.20 kcal/mol	Karton 2011
0.156	2682.8	CH2NH2 (g) + CH4 (g) → CH3NH2 (g) + CH3 (g)	Δ_rH°(0 K) = 12.19 ± 0.20 kcal/mol	Karton 2011
0.151	5419.7	CH2CHNH2 (g) + CH3NH (g) → CH2CHNH (g, anti) + CH3NH2 (g)	Δ_rH°(0 K) = -44.82 ± 2.0 kJ/mol	Klippenstein 2017
0.151	5567.1	(CH3)3N (g) + NH3 (g) → (CH3)2NH (g) + CH3NH2 (g)	Δ_rH°(298.15 K) = 7.82 ± 0.40 kcal/mol	Issoire 1960, as quoted by Cox 1970
0.134	5367.1	[CH3NHCH2]+ (g) + CH3NH2 (g) → [CH2NH2]+ (g) + (CH3)2NH (g)	Δ_rH°(0 K) = 0.460 ± 0.025 eV	Bodi 2006
0.120	5382.6	CH3NCH2 (g) + NH3 (g) → CH2NH (g) + CH3NH2 (g)	Δ_rH°(0 K) = 33.41 ± 2.0 kJ/mol	Klippenstein 2017
0.118	5366.6	CH3NHCH2 (g) + CH3NH2 (g) → CH2NH2 (g) + (CH3)2NH (g)	Δ_rH°(0 K) = 2.15 ± 2.0 kJ/mol	Klippenstein 2017
0.109	5524.6	CH2CHNH2 (g) + CH3CH3 (g) → CH3CHCH2 (g) + CH3NH2 (g)	Δ_rH°(0 K) = 28.47 ± 2.0 kJ/mol	Klippenstein 2017
0.109	9060.2	CH3CH2NH2 (g) + NH3 (g) → 2 CH3NH2 (g)	Δ_rH°(0 K) = 54.20 ± 1.5 kJ/mol	Klippenstein 2017
0.103	2662.5	[CH3NH2]- (g) → CH3NH2 (g)	Δ_rH°(0 K) = -0.954 ± 0.090 eV	Ruscic CBS-n

References

1		B. Ruscic, R. E. Pinzon, M. L. Morton, G. von Laszewski, S. Bittner, S. G. Nijsure, K. A. Amin, M. Minkoff, and A. F. Wagner, Introduction to Active Thermochemical Tables: Several "Key" Enthalpies of Formation Revisited. J. Phys. Chem. A 108, 9979-9997 (2004) [DOI: 10.1021/jp047912y]
2		B. Ruscic, R. E. Pinzon, G. von Laszewski, D. Kodeboyina, A. Burcat, D. Leahy, D. Montoya, and A. F. Wagner, Active Thermochemical Tables: Thermochemistry for the 21^st Century. J. Phys. Conf. Ser. 16, 561-570 (2005) [DOI: 10.1088/1742-6596/16/1/078]
3		B. Ruscic and D. H. Bross, Active Thermochemical Tables (ATcT) values based on ver. 1.172 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		K. L. Caster, N. A. Seifert, B. Ruscic, A. W. Jasper, and K. Prozument, Dynamics of HCN, NHC, and HNCO Formation in the 193 nm Photodissociation of Formamide J. Phys. Chem. A (in press) (2024) [DOI: 10.1021/acs.jpca.4c02232]
5		B. Ruscic, Uncertainty Quantification in Thermochemistry, Benchmarking Electronic Structure Computations, and Active Thermochemical Tables. Int. J. Quantum Chem. 114, 1097-1101 (2014) [DOI: 10.1002/qua.24605]
6		B. Ruscic and D. H. Bross, Thermochemistry Computer Aided Chem. Eng. 45, 3-114 (2019) [DOI: 10.1016/B978-0-444-64087-1.00001-2]

Formula

The aggregate state is given in parentheses following the formula, such as: g - gas-phase, cr - crystal, l - liquid, etc.

Uncertainties

The listed uncertainties correspond to estimated 95% confidence limits, as customary in thermochemistry (see, for example, Ruscic [5] and Ruscic and Bross[6]).
Note that an uncertainty of ± 0.000 kJ/mol indicates that the estimated uncertainty is < ± 0.000₅ kJ/mol.

Website Functionality Credits

The reorganization of the website was developed and implemented by David H. Bross (ANL).
The find function is based on the complete Species Dictionary entries for the appropriate version of the ATcT TN.
The molecule images are rendered by Indigo-depict.
The XYZ renderings are based on Jmol: an open-source Java viewer for chemical structures in 3D. http://www.jmol.org/.

Acknowledgement

This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences under Contract No. DE-AC02-06CH11357.