Selected ATcT [1, 2] enthalpy of formation based on version 1.176 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.172 to include species related to Criegee intermediates that are involved in several ongoing studies[4].

Disulfur

Formula: S2 (g)
CAS RN: 23550-45-0
ATcT ID: 23550-45-0*0
SMILES: S=S
InChI: InChI=1S/S2/c1-2
InChIKey: MAHNFPMIPQKPPI-UHFFFAOYSA-N
Hills Formula: S2

2D Image:

S=S
Aliases: S2; Disulfur; Sulfur dimer; Diatomic sulfur; Sulfur
Relative Molecular Mass: 64.1320 ± 0.0120

   ΔfH°(0 K)   ΔfH°(298.15 K)UncertaintyUnits
127.37127.68± 0.27kJ/mol

3D Image of S2 (g)

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Top contributors to the provenance of ΔfH° of S2 (g)

The 10 contributors listed below account for 91.5% of the provenance of ΔfH° of S2 (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
30.09416.1 S (cr,l) O2 (g) → OSO (g) ΔrH°(298.15 K) = -296.847 ± 0.200 kJ/molEckman 1929, note SO2
16.09563.1 S (cr,l) + 3/2 O2 (g) H2O (cr,l) → OS(O)(OH)2 (aq, 115 H2O) ΔrH°(298.15 K) = -143.85 ± 0.06 kcal/molGood 1960, CODATA Key Vals
11.89563.2 S (cr,l) + 3/2 O2 (g) H2O (cr,l) → OS(O)(OH)2 (aq, 115 H2O) ΔrH°(298.15 K) = -143.92 ± 0.07 kcal/molMansson 1963, CODATA Key Vals
11.19436.1 SO (g) → S (g) O (g) ΔrH°(0 K) = 43275 ± 5 cm-1Clerbaux 1994
5.69401.2 S (cr,l) → S2 (g) ΔrG°(570 K) = 9.483 ± 0.138 (×1.915) kcal/molDrowart 1968, Detry 1967, 3rd Law
4.79602.1 S (cr,l) + 3/2 O2 (g) H2O (cr,l) → OS(O)(OH)2 (aq, 45 H2O) ΔrH°(298.15 K) = -143.67 ± 0.11 kcal/molMcCullough 1957a
4.29401.4 S (cr,l) → S2 (g) ΔrG°(600 K) = 8.57 ± 0.29 (×1.044) kcal/molBraune 1951, West 1929, Gurvich TPIS, 3rd Law
3.29562.1 S (cr,l) + 3/2 O2 (g) H2O (cr,l) → OS(O)(OH)2 (aq, 70 H2O) ΔrH°(298.15 K) = -143.58 ± 0.09 (×1.477) kcal/molMcCullough 1953, CODATA Key Vals
2.29563.3 S (cr,l) + 3/2 O2 (g) H2O (cr,l) → OS(O)(OH)2 (aq, 115 H2O) ΔrH°(298.15 K) = -143.70 ± 0.07 (×2.278) kcal/molWaddington 1956, Mansson 1963, est unc
2.29561.1 OSO (g) + 1/2 O2 (g) H2O (cr,l) → OS(O)(OH)2 (cr,l) ΔrH°(298.15 K) = -231.329 ± 0.040 kJ/molNBS Tables 1989

Top 10 species with enthalpies of formation correlated to the ΔfH° of S2 (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
99.3 SulfurS (g)[S]276.83279.08± 0.14kJ/mol32.0660 ±
0.0060
7704-34-9*0
99.3 Monosulfur anionS- (g)[S-]76.4278.48± 0.14kJ/mol32.0665 ±
0.0060
14337-03-2*0
99.1 Monosulfur cationS+ (g)[S+]1276.421278.21± 0.14kJ/mol32.0655 ±
0.0060
14701-12-3*0
97.5 Sulfur atom dication[S]+2 (g)[S++]3528.183531.88± 0.14kJ/mol32.0649 ±
0.0060
14127-58-3*0
90.0 Sulfur monoxideSO (g)S=O5.956.00± 0.13kJ/mol48.0654 ±
0.0060
13827-32-2*0
90.0 Sulfur dioxideOSO (g)O=S=O-294.20-296.74± 0.13kJ/mol64.0648 ±
0.0060
7446-09-5*0
88.8 Oxosulfur[SO]+ (g)[S+]=O999.26999.87± 0.13kJ/mol48.0649 ±
0.0060
767269-11-4*0
88.4 Sulfonyl cation[OSO]+ (g)O=[S+]=O897.01894.74± 0.13kJ/mol64.0643 ±
0.0060
12439-77-9*0
84.0 Sulfuric acidOS(O)(OH)2 (cr,l)OS(=O)(=O)O-811.89-813.88± 0.13kJ/mol98.0795 ±
0.0061
7664-93-9*500
83.5 Sulfur dioxideOSO (aq, undissoc)O=S=O-320.69± 0.14kJ/mol64.0648 ±
0.0060
7446-09-5*1000

Most Influential reactions involving S2 (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
0.9709395.1 S2 (g) → 2 S (g) ΔrH°(0 K) = 35636.3 ± 2.5 cm-1Ricks 1969, Huber 1979, Green 1997, Frederix 2009
0.9209397.1 S2 (g) → [S2]+ (g) ΔrH°(0 K) = 75580 ± 16 cm-1Hrodmarsson 2021
0.8549398.11 [S2]- (g) → S2 (g) ΔrH°(0 K) = 1.673 ± 0.005 eVFeller 2016a, Feller 2016, est unc
0.2459834.7 SCS (g) → C (g) S2 (g) ΔrH°(0 K) = 172.97 ± 0.30 kcal/molKarton 2011
0.2189508.11 SSS (g) → 3 S2 (g) ΔrH°(0 K) = 22.82 ± 0.60 kcal/molKarton 2011
0.2189506.7 SSS (g) → S2 (g) S (g) ΔrH°(0 K) = 62.26 ± 0.30 kcal/molKarton 2011
0.1219495.8 OSO (g) + 3/2 S2 (g) → 2 SSO (g) ΔrH°(0 K) = -0.01 ± 0.40 (×1.164) kcal/molKarton 2011
0.0949398.1 [S2]- (g) → S2 (g) ΔrH°(0 K) = 1.670 ± 0.015 eVMoran 1988
0.0709834.6 SCS (g) → C (g) S2 (g) ΔrH°(0 K) = 172.84 ± 0.56 kcal/molKarton 2011
0.0699409.11 S2 (g) + 2 H2O (g) → O2 (g) + 2 H2S (g) ΔrH°(0 K) = 75.51 ± 0.25 kcal/molFeller 2008
0.0699409.10 S2 (g) + 2 H2O (g) → O2 (g) + 2 H2S (g) ΔrH°(0 K) = 75.40 ± 0.25 kcal/molKarton 2006, Karton 2011
0.0659495.9 OSO (g) + 3/2 S2 (g) → 2 SSO (g) ΔrH°(0 K) = -0.17 ± 0.25 (×2.538) kcal/molKarton 2006, Karton 2011
0.0599494.10 SSO (g) → S2 (g) O (g) ΔrH°(0 K) = 101.87 ± 0.30 (×1.114) kcal/molKarton 2006
0.0569401.2 S (cr,l) → S2 (g) ΔrG°(570 K) = 9.483 ± 0.138 (×1.915) kcal/molDrowart 1968, Detry 1967, 3rd Law
0.0559508.1 SSS (g) → 3 S2 (g) ΔrG°(573 K) = 20.2 ± 5.0 kJ/molDetry 1967, 3rd Law, est unc
0.0549508.10 SSS (g) → 3 S2 (g) ΔrH°(0 K) = 22.28 ± 1.20 kcal/molKarton 2011
0.0549506.6 SSS (g) → S2 (g) S (g) ΔrH°(0 K) = 61.78 ± 0.60 kcal/molKarton 2011
0.0429401.4 S (cr,l) → S2 (g) ΔrG°(600 K) = 8.57 ± 0.29 (×1.044) kcal/molBraune 1951, West 1929, Gurvich TPIS, 3rd Law
0.0409833.1 SCS (g) → C (graphite) S2 (g) ΔrG°(1235 K) = 19.6 ± 3.1 kJ/molKoref 1910, 3rd Law
0.0409403.4 S2 (g) + 2 H2 (g) → 2 H2S (g) ΔrG°(1515 K) = -31.42 ± 0.80 (×1.719) kJ/molRandall 1918, Gurvich TPIS, 2nd Law


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. 1.176 of the Thermochemical Network (2024); available at ATcT.anl.gov
4   T. L. Nguyen et al, ongoing studies (2024)
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.