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].

Hydrazine

Formula: NH2NH2 (g)

CAS RN: 302-01-2

ATcT ID: 302-01-2*0

SMILES: NN

InChI: InChI=1S/H4N2/c1-2/h1-2H2

InChIKey: OAKJQQAXSVQMHS-UHFFFAOYSA-N

Hills Formula: H4N2

2D Image:

Aliases: NH2NH2; Hydrazine; Dinitrogen tetrahydride; Diazane; Levoxine; Oxytreat 35

Relative Molecular Mass: 32.04524 ± 0.00031

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
111.75	97.60	± 0.44	kJ/mol

3D Image of NH2NH2 (g)

spin ON spin OFF

Top contributors to the provenance of Δ_fH° of NH2NH2 (g)

The 20 contributors listed below account only for 80.4% of the provenance of Δ_fH° of NH2NH2 (g).
A total of 43 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
17.2	1804.10	2 NH3 (g) → NH2NH2 (g) + H2 (g)	Δ_rH°(0 K) = 45.18 ± 0.25 kcal/mol	Karton 2008, Karton 2006
12.0	1799.8	NH2NH2 (g) → 2 N (g) + 4 H (g)	Δ_rH°(0 K) = 404.76 ± 0.30 kcal/mol	Karton 2011, Karton 2008
8.4	1804.1	2 NH3 (g) → NH2NH2 (g) + H2 (g)	Δ_rH°(0 K) = 188.93 ± 1.5 kJ/mol	Klippenstein 2017
8.2	1837.8	NH2NH2 (g) → HNNH (g, trans) + H2 (g)	Δ_rH°(0 K) = 22.78 ± 0.30 kcal/mol	Karton 2011
6.3	1799.10	NH2NH2 (g) → 2 N (g) + 4 H (g)	Δ_rH°(0 K) = 1693.65 ± 1.73 kJ/mol	Feller 2017
4.0	1808.1	NH2NH2 (cr,l) → NH2NH2 (g)	Δ_rH°(298.15 K) = 10.69 ± 0.10 (×5.187) kcal/mol	Scott 1949, apud JANAF 3
3.4	1799.7	NH2NH2 (g) → 2 N (g) + 4 H (g)	Δ_rH°(0 K) = 404.91 ± 0.56 kcal/mol	Karton 2011
3.0	1804.11	2 NH3 (g) → NH2NH2 (g) + H2 (g)	Δ_rH°(0 K) = 187.1 ± 2.5 kJ/mol	Klopper 2010a, est unc
3.0	1799.9	NH2NH2 (g) → 2 N (g) + 4 H (g)	Δ_rH°(0 K) = 405.19 ± 0.6 kcal/mol	Feller 2008, Matus 2006a
2.4	1817.1	NH2NH2 (g) → [NH2NH]+ (g) + H (g)	Δ_rH°(0 K) = 11.112 ± 0.010 eV	Gibson 1985, AE corr, Ruscic 1991b
2.3	1837.7	NH2NH2 (g) → HNNH (g, trans) + H2 (g)	Δ_rH°(0 K) = 23.03 ± 0.56 kcal/mol	Karton 2011
2.1	1799.11	NH2NH2 (g) → 2 N (g) + 4 H (g)	Δ_rH°(0 K) = 1692.7 ± 3.0 kJ/mol	Klopper 2010a
1.3	1816.1	2 NH3 (g) → NH2NH (g) + 3/2 H2 (g)	Δ_rH°(0 K) = 311.40 ± 1.5 kJ/mol	Klippenstein 2017
1.2	1812.1	NH2NH (g) → [NH2NH]+ (g)	Δ_rH°(0 K) = 7.61 ± 0.01 eV	Ruscic 1991b
1.0	1806.1	NH2NH2 (g) → NH3 (g) + NH (g)	Δ_rH°(0 K) = 50.1 ± 1.0 kcal/mol	Klippenstein 2009, est unc
1.0	1805.10	NH2NH2 (g) → 2 NH2 (g)	Δ_rH°(0 K) = 63.7 ± 1.0 kcal/mol	Klippenstein 2009, est unc
0.7	1849.1	NH2NH2 (g) → NNH2 (g) + H2 (g)	Δ_rH°(0 K) = 47.1 ± 1.0 kcal/mol	Klippenstein 2009, est unc
0.7	1804.9	2 NH3 (g) → NH2NH2 (g) + H2 (g)	Δ_rH°(0 K) = 45.08 ± 1.2 kcal/mol	Ruscic W1RO
0.7	1848.1	NH2NH2 (g) → HNNH (g, trans) + H2 (g)	Δ_rH°(0 K) = 23.1 ± 1.0 kcal/mol	Klippenstein 2009, est unc
0.7	1814.9	[NH2NH]+ (g) → 2 N (g) + 3 H (g)	Δ_rH°(0 K) = 148.34 ± 0.8 kcal/mol	Matus 2006a, est unc

Top 10 species with enthalpies of formation correlated to the Δ_fH° of NH2NH2 (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
39.5	Diazenium	[NH2NH]+ (g)	968.67	957.41	± 0.73	kJ/mol	31.03675 ± 0.00025	37369-93-0*0
26.2	Hydrazino	NH2NH (g)	234.79	224.26	± 0.69	kJ/mol	31.03730 ± 0.00025	13598-46-4*0
19.8	(E)-Diazene	HNNH (g, trans)	207.17	200.03	± 0.40	kJ/mol	30.02936 ± 0.00020	15626-43-4*0
19.8	Diazene	HNNH (g, trans-cis-iso equilib)	207.17	200.03	± 0.40	kJ/mol	30.02936 ± 0.00020	3618-05-1*0
19.8	Diazene	HNNH (g, trans-cis equilib)	207.17	200.03	± 0.40	kJ/mol	30.02936 ± 0.00020	3618-05-1*1
13.2	Hydraziniumyl	[NH2NH2]+ (g)	886.7	873.3	± 2.0	kJ/mol	32.04469 ± 0.00031	20771-51-1*0
12.4	Nitrosamine	NH2NO (g)	85.83	76.95	± 0.95	kJ/mol	46.02876 ± 0.00036	35576-91-1*0
12.2	Isodiazene	NNH2 (g)	307.57	300.49	± 0.60	kJ/mol	30.02936 ± 0.00020	28647-38-3*0
11.6	(E)-Diazene cation	[HNNH]+ (g, trans)	1132.53	1125.59	± 0.64	kJ/mol	30.02881 ± 0.00020	59952-06-6*0
11.6	Diazene cation	[HNNH]+ (g, trans-iso-cis equilib)	1132.53	1125.87	± 0.64	kJ/mol	30.02881 ± 0.00020	76986-17-9*0

Most Influential reactions involving NH2NH2 (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
0.702	1801.6	[NH2NH2]- (g) → NH2NH2 (g)	Δ_rH°(0 K) = -1.227 ± 0.050 eV	Ruscic W1RO
0.503	1817.1	NH2NH2 (g) → [NH2NH]+ (g) + H (g)	Δ_rH°(0 K) = 11.112 ± 0.010 eV	Gibson 1985, AE corr, Ruscic 1991b
0.265	1800.10	NH2NH2 (g) → [NH2NH2]+ (g)	Δ_rH°(0 K) = 8.025 ± 0.040 eV	Ruscic W1RO
0.216	1801.5	[NH2NH2]- (g) → NH2NH2 (g)	Δ_rH°(0 K) = -1.330 ± 0.090 eV	Ruscic CBS-n
0.201	9198.4	2 NH2NO (g) → NH2NH2 (g) + ONNO (g)	Δ_rH°(0 K) = 27.70 ± 1.0 kcal/mol	Ruscic CBS-n
0.177	1837.8	NH2NH2 (g) → HNNH (g, trans) + H2 (g)	Δ_rH°(0 K) = 22.78 ± 0.30 kcal/mol	Karton 2011
0.175	1804.10	2 NH3 (g) → NH2NH2 (g) + H2 (g)	Δ_rH°(0 K) = 45.18 ± 0.25 kcal/mol	Karton 2008, Karton 2006
0.121	1799.8	NH2NH2 (g) → 2 N (g) + 4 H (g)	Δ_rH°(0 K) = 404.76 ± 0.30 kcal/mol	Karton 2011, Karton 2008
0.119	9198.3	2 NH2NO (g) → NH2NH2 (g) + ONNO (g)	Δ_rH°(0 K) = 28.09 ± 1.3 kcal/mol	Ruscic CBS-n
0.108	9198.1	2 NH2NO (g) → NH2NH2 (g) + ONNO (g)	Δ_rH°(0 K) = 28.36 ± 1.1 (×1.242) kcal/mol	Ruscic G3X
0.085	1804.1	2 NH3 (g) → NH2NH2 (g) + H2 (g)	Δ_rH°(0 K) = 188.93 ± 1.5 kJ/mol	Klippenstein 2017
0.079	1800.6	NH2NH2 (g) → [NH2NH2]+ (g)	Δ_rH°(0 K) = 8.035 ± 0.073 eV	Ruscic G4
0.075	1800.9	NH2NH2 (g) → [NH2NH2]+ (g)	Δ_rH°(0 K) = 7.988 ± 0.075 eV	Ruscic CBS-n
0.074	9198.2	2 NH2NO (g) → NH2NH2 (g) + ONNO (g)	Δ_rH°(0 K) = 28.63 ± 1.0 (×1.646) kcal/mol	Ruscic G4
0.066	1800.11	NH2NH2 (g) → [NH2NH2]+ (g)	Δ_rH°(0 K) = 8.07 ± 0.08 eV	Rocha 2008, est unc
0.064	1799.10	NH2NH2 (g) → 2 N (g) + 4 H (g)	Δ_rH°(0 K) = 1693.65 ± 1.73 kJ/mol	Feller 2017
0.056	1817.10	NH2NH2 (g) → [NH2NH]+ (g) + H (g)	Δ_rH°(0 K) = 11.128 ± 0.030 eV	Matus 2006a, est unc
0.051	1837.7	NH2NH2 (g) → HNNH (g, trans) + H2 (g)	Δ_rH°(0 K) = 23.03 ± 0.56 kcal/mol	Karton 2011
0.049	1800.5	NH2NH2 (g) → [NH2NH2]+ (g)	Δ_rH°(0 K) = 8.045 ± 0.093 eV	Ruscic G3X
0.047	1801.3	[NH2NH2]- (g) → NH2NH2 (g)	Δ_rH°(0 K) = -1.440 ± 0.061 (×3.152) eV	Ruscic G4

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.