Selected ATcT [1, 2] enthalpy of formation based on version 1.122g of the Thermochemical Network [3]

This version of ATcT results was generated from an expansion of version 1.122e [4] to include results centered on the determination of the appearance energy of CH3+ from CH4. [5].

Species Name Formula Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass		 ATcT ID
WaterH2O (g)O-238.932-241.836± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*0

Representative Geometry of H2O (g)

spin ON           spin OFF
          

Top contributors to the provenance of ΔfH° of H2O (g)

The 20 contributors listed below account only for 67.2% of the provenance of ΔfH° of H2O (g).
A total of 237 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
42.3118.2 1/2 O2 (g) + H2 (g) → H2O (cr,l) ΔrH°(298.15 K) = -285.8261 ± 0.040 kJ/molRossini 1939, Rossini 1931, Rossini 1931b, note H2Oa, Rossini 1930
3.51888.1 2 H2 (g) + C (graphite) → CH4 (g) ΔrG°(1165 K) = 37.521 ± 0.068 kJ/molSmith 1946, note COf, 3rd Law
3.31887.4 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.61 ± 0.21 kJ/molDale 2002
2.3161.1 [OH]- (g) → O- (g) + H (g) ΔrH°(0 K) = 4.7796 ± 0.0010 (×1.756) eVMartin 2001, est unc
2.11887.6 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.44 ± 0.26 kJ/molGOMB Ref Calorimeter, Alexandrov 2002
1.91444.1 N2 (g) + 3 H2O (cr,l) + 2 H+ (aq) → 3/2 O2 (g) + 2 [NH4]+ (aq) ΔrH°(298.15 K) = 141.292 ± 0.119 kcal/molVanderzee 1972c
1.31975.1 CH3CH3 (g) + 7/2 O2 (g) → 2 CO2 (g) + 3 H2O (cr,l) ΔrH°(298.15 K) = -1560.68 ± 0.25 kJ/molPittam 1972
1.21887.5 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.43 ± 0.35 kJ/molAlexandrov 2002a, Alexandrov 2002
1.21887.1 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(303.15 K) = -889.849 ± 0.350 kJ/molRossini 1931a, Rossini 1931b, Prosen 1945, Rossini 1940, note CH4
0.91817.3 CO (g) + H2O (g) → CO2 (g) + H2 (g) ΔrG°(893 K) = -6.369 ± 0.283 kJ/molMeyer 1938, note COi, 3rd Law
0.81810.2 CO (g) → C+ (g) + O (g) ΔrH°(0 K) = 22.3713 ± 0.0015 eVNg 2007
0.81887.2 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.699 ± 0.430 kJ/molPittam 1972, note CH4a
0.7214.4 H2O2 (g) → 2 H (g) + 2 O (g) ΔrH°(0 K) = 1054.84 ± 0.56 kJ/molHarding 2008
0.7228.3 H2O2 (cr,l) → H2O (cr,l) + 1/2 O2 (g) ΔrH°(293.15 K) = -23.48 ± 0.03 (×1.915) kcal/molRoth 1930, est unc
0.71264.4 NNO (g) + CO (g) → CO2 (g) + N2 (g) ΔrH°(293.15 K) = -365.642 ± 0.243 kJ/molFenning 1933, note N2Oa
0.6118.3 1/2 O2 (g) + H2 (g) → H2O (cr,l) ΔrH°(303.4 K) = -285.67 ± 0.32 kJ/molKing 1968, note H2Ob
0.52396.2 CH3OH (g) + 3/2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -182.72 ± 0.05 (×1.242) kcal/molRossini 1932a, Domalski 1972, Weltner 1951, Rossini 1934a, note old units, mw conversion
0.5228.4 H2O2 (cr,l) → H2O (cr,l) + 1/2 O2 (g) ΔrH°(293.15 K) = -23.47 ± 0.02 (×3.364) kcal/molMatheson 1929, est unc
0.5232.1 H2O2 (g) → 2 OH (g) ΔrH°(0 K) = 17051.8 ± 3.4 cm-1Luo 1992
0.51440.3 (NH4)NO3 (cr,l) → N2 (g) + 1/2 O2 (g) + 2 H2O (cr,l) ΔrH°(293.65 K) = -49.44 ± 0.06 kcal/molBecker 1934

Top 10 species with enthalpies of formation correlated to the ΔfH° of H2O (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 Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass		 ATcT ID
100.0 WaterH2O (g, para)O-238.932-241.836± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*2
100.0 Oxonium[H3O]+ (aq)[OH3+]-285.830± 0.027kJ/mol19.02267 ±
0.00037		13968-08-6*800
100.0 WaterH2O (cr,l)O-286.302-285.830± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*500
100.0 WaterH2O (cr, l, eq.press.)O-286.304-285.832± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*499
100.0 WaterH2O (l)O-285.830± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*590
100.0 WaterH2O (l, eq.press.)O-285.832± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*589
100.0 WaterH2O (g, ortho)O-238.648-241.836± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*1
99.9 WaterH2O (cr)O-286.302-292.743± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*510
99.9 WaterH2O (cr, eq.press.)O-286.304-292.745± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*509
99.9 HydroxylOH (g)[OH]37.24837.488± 0.027kJ/mol17.00734 ±
0.00031		3352-57-6*0

Most Influential reactions involving H2O (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
1.000113.1 H2O (g, para) → H2O (g) ΔrH°(0 K) = 0. ± 0. cm-1Tennyson 2001
0.9312709.1 CH3CHCH2 (g) + [OH]- (g) → [CH2CHCH2]- (g) + H2O (g) ΔrG°(300 K) = -0.30 ± 0.03 kcal/molEllison 1996
0.790134.5 [H2O]- (g) → H2O (g) ΔrH°(0 K) = -1.947 ± 0.050 eVRuscic W1RO
0.7101638.8 NO (g) + ONO (g) + H2O (g) → 2 HONO (g) ΔrG°(298.15 K) = -1.44 ± 0.10 kJ/molVosper 1976, 3rd Law
0.6641040.1 BrOBr (g) + H2O (g) → 2 HOBr (g) ΔrG°(298.15 K) = 9.70 ± 1.2 kJ/molHassanzadeh 1997, Orlando 1995
0.609156.3 H2O (g) → OH (g) + H (g) ΔrH°(0 K) = 41145.92 ± 0.12 cm-1Boyarkin 2013
0.597206.6 (H2O)3 (g) → 3 H2O (g) ΔrH°(0 K) = 3855 ± 20 cm-1Wang 2011, Anderson 2004, Wang 2011a, Samanta 2014
0.502110.1 H2O (g) → [H2O]+ (g) ΔrH°(0 K) = 101766.3 ± 1.0 cm-1Lauzin 2015
0.4562416.7 CH2OH2 (g) → CH2 (g, singlet) + H2O (g) ΔrH°(0 K) = 9.01 ± 0.17 kcal/molNguyen 2015a
0.4071716.6 HOONO (g, trans, perp) + H2O (g) → HONO (g, trans) + H2O2 (g) ΔrH°(0 K) = 6.93 ± 0.15 kcal/molMcGrath 2005
0.389156.2 H2O (g) → OH (g) + H (g) ΔrH°(0 K) = 41145.94 ± 0.15 cm-1Maksyutenko 2006
0.349110.2 H2O (g) → [H2O]+ (g) ΔrH°(0 K) = 101766.8 ± 1.2 cm-1Merkt 1998
0.336125.5 H2O (l, eq.press.) → H2O (g) ΔrG°(298.15 K) = 8.560013 ± 0.000348 kJ/molWagner 2002
0.309128.4 H2O (l, eq.press.) → H2O (g) ΔrG°(300 K) = 8.340252 ± 0.000363 kJ/molWagner 2002
0.2951547.1 NH2OH (g, trans) + H2O (g) → H2O2 (g) + NH3 (g) ΔrH°(0 K) = 24.9 ± 0.2 kcal/molFeller 2003, est unc
0.2941546.1 NH2OH (g, trans) + H2 (g) → H2O (g) + NH3 (g) ΔrH°(0 K) = -58.4 ± 0.2 kcal/molFeller 2003, est unc
0.2891671.1 2 ONO (g) + 1/2 O2 (g) + H2O (g) → 2 HON(O)O (g) ΔrG°(371 K) = -6.04 ± 0.63 kJ/molJones 1943, 3rd Law
0.265205.3 (H2O)3 (g) → (H2O)2 (g) + H2O (g) ΔrH°(0 K) = 2726 ± 30 cm-1Wang 2011, Samanta 2014
0.264136.4 [(H)(OH)]- (g, vdW ?) → H2O (g) ΔrH°(0 K) = -2.807 ± 0.061 eVRuscic G4
0.1913643.4 HCO (g) + 2 OH (g) → HCOO (g, cis) + H2O (g) ΔrH°(0 K) = -1.93 ± 1.60 kcal/molRuscic G4
References (for your convenience, also available in RIS and BibTex format)
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 21st 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. 1.122g of the Thermochemical Network (2019); available at ATcT.anl.gov
4   J. P. Porterfield, D. H. Bross, B. Ruscic, J. H. Thorpe, T. L. Nguyen, J. H. Baraban, J. F. Stanton, J. W. Daily, and G. B. Ellison,
Thermal Decomposition of Potential Ester Biofuels, Part I: Methyl Acetate and Methyl Butanoate.
J. Chem. Phys. A 121, 4658-4677 (2017) [DOI: 10.1021/acs.jpca.7b02639] (Veronica Vaida Festschrift)
5   Y.-C. Chang, B. Xiong, D. H. Bross, B. Ruscic, and C. Y. Ng,
A Vacuum Ultraviolet laser Pulsed Field Ionization-Photoion Study of Methane (CH4): Determination of the Appearance Energy of Methylium From Methane with Unprecedented Precision and the Resulting Impact on the Bond Dissociation Energies of CH4 and CH4+.
Phys. Chem. Chem. Phys. 19, 9592-9605 (2017) [DOI: 10.1039/c6cp08200a] (part of 2017 PCCP Hot Articles collection)
6   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]
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 [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.