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

This version of ATcT results was generated from an expansion of version 1.122q [4, 5] to include a non-rigid rotor anharmonic oscillator (NRRAO) partition function for hydroxymethyl. [6], as well as data on 42 additional species, some of which are related to soot formation mechanisms.

Species Name Formula Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass
ATcT ID
FormaldehydeCH2O (g, singlet)C=O-105.376-109.214± 0.096kJ/mol30.02598 ±
0.00087
50-00-0*2

Representative Geometry of CH2O (g, singlet)

spin ON           spin OFF
          

Top contributors to the provenance of ΔfH° of CH2O (g, singlet)

The 9 contributors listed below account for 49.6% of the provenance of ΔfH° of CH2O (g, singlet).

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
20.92627.11 [HCO]+ (g) → H+ (g) CO (g) ΔrH°(0 K) = 586.51 ± 0.2 kJ/molCzako 2008
10.72557.3 CO (g) H2 (g) → CH2O (g) ΔrH°(0 K) = 8.39 ± 0.28 kJ/molCzako 2009
3.12556.8 CH2O (g) → CH4 (g) CO2 (g) ΔrH°(0 K) = -59.44 ± 0.25 kcal/molKarton 2006
3.12556.7 CH2O (g) → CH4 (g) CO2 (g) ΔrH°(0 K) = -59.44 ± 0.25 kcal/molKarton 2006
3.02629.9 CO (g) [NH4]+ (g) → [HCO]+ (g) NH3 (g) ΔrH°(0 K) = 259.89 ± 0.3 kJ/molCzako 2008
2.42537.1 [CH2OH]+ (g) → CH2O (g) H+ (g) ΔrH°(0 K) = 704.98 ± 0.39 kJ/molCzako 2009
2.32620.9 HCO (g) → H (g) O (g) C (g) ΔrH°(0 K) = 1132.68 ± 0.56 kJ/molHarding 2008
2.12556.6 CH2O (g) → CH4 (g) CO2 (g) ΔrH°(0 K) = -59.52 ± 0.30 kcal/molKarton 2006
1.72559.1 CH2O (g) O2 (g) → CO2 (g) H2O (cr,l) ΔrH°(299.65 K) = -570.69 ± 0.40 (×1.719) kJ/molFletcher 1970, note std dev

Top 10 species with enthalpies of formation correlated to the ΔfH° of CH2O (g, singlet)

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 FormaldehydeCH2O (g)C=O-105.376-109.214± 0.096kJ/mol30.02598 ±
0.00087
50-00-0*0
100.0 FormaldehydeCH2O (g, triplet)C=O196.015192.684± 0.096kJ/mol30.02598 ±
0.00087
50-00-0*1
99.6 FormylHCO (g)[CH]=O41.39441.770± 0.096kJ/mol29.01804 ±
0.00086
2597-44-6*0
99.4 Oxomethylium[HCO]+ (g)[CH+]=O827.770827.185± 0.096kJ/mol29.01749 ±
0.00086
17030-74-9*0
98.7 Formaldehyde cation[CH2O]+ (g)C=[O+]944.866941.245± 0.097kJ/mol30.02543 ±
0.00087
54288-05-0*0
23.7 HydroxymethyleneHCOH (g)[CH]O112.68108.92± 0.27kJ/mol30.02598 ±
0.00087
19710-56-6*0
23.7 HydroxymethyleneHCOH (g, trans)[CH]O112.68108.91± 0.27kJ/mol30.02598 ±
0.00087
19710-56-6*1
23.1 HydroxymethyleneHCOH (g, cis)[CH]O131.10127.36± 0.29kJ/mol30.02598 ±
0.00087
19710-56-6*2
21.3 Formyl anion[HCO]- (g)[CH-]=O11.6011.98± 0.44kJ/mol29.01859 ±
0.00086
57340-31-5*0
20.2 CarbonC (g)[C]711.398716.883± 0.045kJ/mol12.01070 ±
0.00080
7440-44-0*0

Most Influential reactions involving CH2O (g, singlet)

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
1.0002563.1 CH2O (g, singlet) → CH2O (g) ΔrH°(0 K) = 0 ± 0 cm-1triv, Herzberg 1966, Ruscic W1RO, Ruscic G4
0.9992564.1 CH2O (g, singlet) → CH2O (g, triplet) ΔrH°(0 K) = 25194.28 ± 0.02 cm-1Raynes 1966, Herzberg 1966, Smith 1962, note unc2
0.0003833.4 CH2OO (g) O2 (g, singlet) → CH2O (g, singlet) OOO (g) ΔrH°(0 K) = -45.01 ± 1.3 (×3.914) kcal/molRuscic CBS-n
0.0003833.3 CH2OO (g) O2 (g, singlet) → CH2O (g, singlet) OOO (g) ΔrH°(0 K) = -45.14 ± 1.6 (×3.221) kcal/molRuscic CBS-n
0.0003833.5 CH2OO (g) O2 (g, singlet) → CH2O (g, singlet) OOO (g) ΔrH°(0 K) = -45.48 ± 1.2 (×4.655) kcal/molRuscic W1RO
0.0003833.2 CH2OO (g) O2 (g, singlet) → CH2O (g, singlet) OOO (g) ΔrH°(0 K) = -45.86 ± 1.3 (×4.555) kcal/molRuscic G4
0.0003833.1 CH2OO (g) O2 (g, singlet) → CH2O (g, singlet) OOO (g) ΔrH°(0 K) = -45.99 ± 1.4 (×4.362) kcal/molRuscic G3X
0.0002564.2 CH2O (g, singlet) → CH2O (g, triplet) ΔrH°(0 K) = 25194 ± 1 cm-1Herzberg 1966, Smith 1962, est unc
0.0002564.3 CH2O (g, singlet) → CH2O (g, triplet) ΔrH°(0 K) = 25200.2 ± 1 (×6.037) cm-1Robinson 1958, Herzberg 1966, Raynes 1966, est unc
0.0002564.4 CH2O (g, singlet) → CH2O (g, triplet) ΔrH°(0 K) = 25243.0 ± 50 cm-1Hodges 1958, est unc


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 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. 1.122r of the Thermochemical Network (2021); available at ATcT.anl.gov
4   D. Feller, D. H. Bross, and B. Ruscic,
Enthalpy of Formation of C2H2O4 (Oxalic Acid) from High-Level Calculations and the Active Thermochemical Tables Approach.
J. Phys. Chem. A 123, 3481-3496 (2019) [DOI: 10.1021/acs.jpca.8b12329]
5   B. K. Welch, R. Dawes, D. H. Bross, and B. Ruscic,
An Automated Thermochemistry Protocol Based on Explicitly Correlated Coupled-Cluster Theory: The Methyl and Ethyl Peroxy Families.
J. Phys. Chem. A 123, 5673-5682 (2019) [DOI: 10.1021/acs.jpca.8b12329]
6   D. H. Bross, H.-G. Yu, L. B. Harding, and B. Ruscic,
Active Thermochemical Tables: The Partition Function of Hydroxymethyl (CH2OH) Revisited.
J. Phys. Chem. A 123, 4212-4231 (2019) [DOI: 10.1021/acs.jpca.9b02295]
7   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.