Selected ATcT [1, 2] enthalpy of formation based on version 1.122h 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
Cyanogen iodide cation[ICN]+ (g)I[C+]#N1271.51271.3± 1.6kJ/mol152.92136 ±
0.00080
34749-78-5*0

Representative Geometry of [ICN]+ (g)

spin ON           spin OFF
          

Top contributors to the provenance of ΔfH° of [ICN]+ (g)

The 14 contributors listed below account for 90.3% of the provenance of ΔfH° of [ICN]+ (g).

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
43.12382.2 ICN (g) → I (g) CN (g) ΔrH°(0 K) = 26980 ± 200 cm-1Costen 1999, note unc2
9.72381.2 ICN (g) CH3Br (g) → BrCN (g) CH3I (g) ΔrH°(0 K) = 2.43 ± 1.0 kcal/molRuscic unpub
8.02381.3 ICN (g) CH3Br (g) → BrCN (g) CH3I (g) ΔrH°(0 K) = 2.43 ± 1.1 kcal/molRuscic unpub
6.92382.1 ICN (g) → I (g) CN (g) ΔrH°(0 K) = 26580 ± 500 cm-1Nadler 1985
6.72381.1 ICN (g) CH3Br (g) → BrCN (g) CH3I (g) ΔrH°(0 K) = 2.40 ± 1.2 kcal/molRuscic unpub
3.92382.4 ICN (g) → I (g) CN (g) ΔrH°(0 K) = 26200 ± 400 (×1.646) cm-1Black 1990, note unc2
2.52383.1 ICN (g) → I+ (g) CN (g) ΔrH°(0 K) = 13.679 ± 0.045 (×2.278) eVDibeler 1967b, AE corr, est unc
1.42374.2 ICN (g) H2 (g) → HCN (g) HI (g) ΔrH°(0 K) = -15.93 ± 3.1 kcal/molRuscic unpub
1.42378.2 ICN (g) CH4 (g) → HCN (g) CH3I (g) ΔrH°(0 K) = -1.03 ± 3.1 kcal/molRuscic unpub
1.32374.3 ICN (g) H2 (g) → HCN (g) HI (g) ΔrH°(0 K) = -15.84 ± 3.2 kcal/molRuscic unpub
1.32378.3 ICN (g) CH4 (g) → HCN (g) CH3I (g) ΔrH°(0 K) = -0.97 ± 3.2 kcal/molRuscic unpub
1.22374.1 ICN (g) H2 (g) → HCN (g) HI (g) ΔrH°(0 K) = -14.57 ± 3.4 kcal/molRuscic unpub
1.22378.1 ICN (g) CH4 (g) → HCN (g) CH3I (g) ΔrH°(0 K) = -0.05 ± 3.4 kcal/molRuscic unpub
1.02377.2 ICN (g) HBr (g) → BrCN (g) HI (g) ΔrH°(0 K) = 5.21 ± 3.1 kcal/molRuscic unpub

Top 10 species with enthalpies of formation correlated to the ΔfH° of [ICN]+ (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
99.8 Cyanogen iodideICN (g)IC#N222.7222.2± 1.6kJ/mol152.92191 ±
0.00080
506-78-5*0
32.5 Isocyanogen iodideINC (g)IN=[C]341.8342.1± 4.9kJ/mol152.92191 ±
0.00080
66004-32-8*0
25.0 Cyanogen bromideBrCN (g)BrC#N186.7180.2± 1.1kJ/mol105.9214 ±
0.0013
506-68-3*0
24.9 Cyanogen bromide cation[BrCN]+ (g)Br[C+]#N1331.31325.0± 1.1kJ/mol105.9209 ±
0.0013
34749-77-4*0
7.7 Isocyanogen bromideBrNC (g)BrN=[C]341.2335.4± 3.4kJ/mol105.9214 ±
0.0013
65997-98-0*0
6.5 NitrilomethylCN (g)[C]#N436.73440.01± 0.15kJ/mol26.01744 ±
0.00080
2074-87-5*0
6.4 Cyanogen bromide anion[BrCN]- (g)BrC#[N-]57.954.2± 3.8kJ/mol105.9220 ±
0.0013
54092-05-6*0
5.6 Isocyanogen bromide anion[BrNC]- (g)BrN=[C-]105.0101.8± 4.6kJ/mol105.9220 ±
0.0013
*238754-53-5*0
4.8 Cyanogen chlorideClCN (g)ClC#N134.94135.64± 0.46kJ/mol61.4701 ±
0.0012
506-77-4*0
4.5 Cyanic fluorideFCN (g)FC#N8.799.12± 0.71kJ/mol45.01584 ±
0.00080
1495-50-7*0

Most Influential reactions involving [ICN]+ (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
0.9962384.1 ICN (g) → [ICN]+ (g) ΔrH°(0 K) = 10.870 ± 0.001 eVMyer 1970a
0.0022384.2 ICN (g) → [ICN]+ (g) ΔrH°(0 K) = 10.87 ± 0.02 eVDibeler 1967b
0.0002384.4 ICN (g) → [ICN]+ (g) ΔrH°(0 K) = 10.91 ± 0.02 (×2) eVHeilbronner 1970
0.0002384.3 ICN (g) → [ICN]+ (g) ΔrH°(0 K) = 10.91 ± 0.05 eVLake 1970, 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. 1.122h of the Thermochemical Network (2020); 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.