Sulfur dimer
- Formula: S2
- Molecular weight: 64.130
- IUPAC Standard InChIKey: MAHNFPMIPQKPPI-UHFFFAOYSA-N
- CAS Registry Number: 23550-45-0
- Chemical structure:
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Gas phase thermochemistry data
Go To: Top, Reaction thermochemistry data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 30.736 ± 0.072 | kcal/mol | Review | Cox, Wagman, et al., 1984 | CODATA Review value |
ΔfH°gas | 30.736 | kcal/mol | Review | Chase, 1998 | Data last reviewed in September, 1977 |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 54.5332 ± 0.0024 | cal/mol*K | Review | Cox, Wagman, et al., 1984 | CODATA Review value |
S°gas,1 bar | 54.539 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in September, 1977 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = A + B*t + C*t2 + D*t3 +
E/t2
H° − H°298.15= A*t + B*t2/2 +
C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 −
E/(2*t2) + G
Cp = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 298. to 6000. |
---|---|
A | 8.009831 |
B | 1.210651 |
C | -0.253267 |
D | 0.021488 |
E | -0.050648 |
F | 28.12751 |
G | 63.59749 |
H | 30.73621 |
Reference | Chase, 1998 |
Comment | Data last reviewed in September, 1977 |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
B - John E. Bartmess
RCD - Robert C. Dunbar
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
By formula: (HS2- • 4294967295S2) + S2 = HS2-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 81.6 ± 3.7 | kcal/mol | N/A | Entfellner and Boesl, 2009 | gas phase; B |
ΔrH° | 46.7 ± 3.7 | kcal/mol | Ther | Moran and Ellison, 1988 | gas phase; B |
By formula: (OS2- • 4294967295S2) + S2 = OS2-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 113.29 ± 0.39 | kcal/mol | N/A | Nimlos and Ellison, 1986 | gas phase; B |
By formula: (V+ • S2) + S2 = (V+ • 2S2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 68.4 ± 4.4 | kcal/mol | CIDT | Schroeder, Kretzschmar, et al., 2003 | RCD |
By formula: (Mo+ • S2) + S2 = (Mo+ • 2S2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 71.6 ± 3.0 | kcal/mol | CIDT | Schroeder, Kretzschmar, et al., 2003 | RCD |
By formula: V+ + S2 = (V+ • S2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 74.8 ± 3.2 | kcal/mol | CIDT | Schroeder, Kretzschmar, et al., 2003 | RCD |
By formula: Mo+ + S2 = (Mo+ • S2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 78.7 ± 2.5 | kcal/mol | CIDT | Schroeder, Kretzschmar, et al., 2003 | RCD |
References
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A.,
CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]
Chase, 1998
Chase, M.W., Jr.,
NIST-JANAF Themochemical Tables, Fourth Edition,
J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]
Entfellner and Boesl, 2009
Entfellner, M.; Boesl, U.,
Photodetachment-photoelectron spectroscopy of disulfanide: the ground and first excited electronic state of HS2 and DS2,
Phys. Chem. Chem. Phys., 2009, 11, 15, 2657-2662, https://doi.org/10.1039/b820174a
. [all data]
Moran and Ellison, 1988
Moran, S.; Ellison, G.B.,
Photoelectron Spectroscopy of Sulfur Ions,
J. Phys. Chem., 1988, 92, 7, 1794, https://doi.org/10.1021/j100318a021
. [all data]
Nimlos and Ellison, 1986
Nimlos, M.R.; Ellison, G.B.,
Photoelectron spectroscopy of SO2-, S3-, and S2O-,
J. Phys. Chem., 1986, 90, 2574. [all data]
Schroeder, Kretzschmar, et al., 2003
Schroeder, D.; Kretzschmar, I.; Schwarz; Armentrout, P.B.,
Structure, Thermochemistry, and Reactivityof MSn+ Cations (M=V,Mo; n=1-3) in the Gas Phase,
Int. J. Mass Spectrom., 2003, 228, 2-3, 439, https://doi.org/10.1016/S1387-3806(03)00137-4
. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, References
- Symbols used in this document:
S°gas,1 bar Entropy of gas at standard conditions (1 bar) ΔfH°gas Enthalpy of formation of gas at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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