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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Reaction thermochemistry data
Go To: Top, Gas phase ion energetics data, Ion clustering 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 |
Gas phase ion energetics data
Go To: Top, Reaction thermochemistry data, Ion clustering data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data evaluated as indicated in comments:
L - Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to S2+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 9.356 ± 0.002 | eV | N/A | N/A | L |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
1.670 ± 0.015 | LPES | Moran and Ellison, 1988 | B |
1.663 ± 0.040 | LPES | Celotta, Bennett, et al., 1974 | B |
1.565 ± 0.050 | LPD | Hunsicker, Jones, et al., 1995 | B |
>0.86 ± 0.10 | R-A | Dillard and Franklin, 1968 | S- + COS -> S2- + CO. Also S2- + COS -> S3- + CO, etc. to n=6; B |
>2.50 ± 0.80 | EIAE | Thynne, 1972 | From CS2; B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.4 | PE | Bender, Carnovale, et al., 1988 | LL |
9.356 ± 0.002 | PI | Liao and Ng, 1986 | LBLHLM |
9.6 ± 0.2 | EI | Rosinger, Grade, et al., 1983 | LBLHLM |
9.5 ± 0.2 | EI | Grade, Wienecke, et al., 1983 | LBLHLM |
9.5 ± 0.3 | EI | Lau, Brittain, et al., 1982 | LBLHLM |
9.38 ± 0.03 | DER | Coppens, Reynaert, et al., 1979 | LLK |
9.36 ± 0.02 | EI | Tal'roze, Butkovskaya, et al., 1978 | LLK |
9.8 ± 0.3 | EI | Smoes, Drowart, et al., 1977 | LLK |
10.1 ± 0.3 | EI | Piacente, Bardi, et al., 1976 | LLK |
9.4 ± 0.1 | EI | Hildenbrand, 1975 | LLK |
9.38 ± 0.01 | PE | Golob, Jonathan, et al., 1975 | LLK |
9.30 | PE | Berkowitz, 1975 | LLK |
9.8 ± 0.5 | EI | Muenow and Margrave, 1972 | LLK |
9.42 ± 0.10 | EI | Hildenbrand, 1972 | LLK |
9.40 ± 0.05 | S | Donovan, Husain, et al., 1970 | RDSH |
9.32 | S | Barrow, duParcq, et al., 1969 | RDSH |
9.36 ± 0.02 | PI | Berkowitz and Lifshitz, 1968 | RDSH |
9.55 | PE | Wu and Fehlner, 1976 | Vertical value; LLK |
9.56 | PE | Berkowitz, 1975 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
S+ | 14.732 ± 0.005 | S | PI | Liao and Ng, 1986 | LBLHLM |
S+ | 13.5 ± 0.5 | S | EI | Piacente, Bardi, et al., 1976 | LLK |
S+ | 14.74 ± 0.01 | S | PI | Berkowitz and Chupka, 1969 | RDSH |
Anion protonation reactions
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 329.9 ± 3.7 | kcal/mol | D-EA | Moran and Ellison, 1988 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | >344.60 | kcal/mol | IMRB | Goodings, Bohme, et al., 1986 | gas phase; S- deprotonates H2S, Sn- for n≥2, does not.; B |
Ion clustering data
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics 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. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering 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: Mo+ + S2 = (Mo+ • S2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 78.7 ± 2.5 | 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: (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 = (V+ • S2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 74.8 ± 3.2 | kcal/mol | CIDT | Schroeder, Kretzschmar, et al., 2003 | RCD |
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 |
References
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
Celotta, Bennett, et al., 1974
Celotta, R.S.; Bennett, R.A.; Hall, J.L.,
Laser Photodetachment Determination of the Electron Affinities of OH, NH2, NH, SO2, and S2,
J. Chem. Phys., 1974, 60, 5, 1740, https://doi.org/10.1063/1.1681268
. [all data]
Hunsicker, Jones, et al., 1995
Hunsicker, S.; Jones, R.O.; Gantefor, G.,
Rings and chains in sulfur cluster anions S- to S-9(-): Theory (simulated annealing) and experiment (photoelectron detachment),
J. Chem. Phys., 1995, 102, 15, 5917, https://doi.org/10.1063/1.469326
. [all data]
Dillard and Franklin, 1968
Dillard, J.G.; Franklin, J.L.,
Ion-Molecule Reactions of Negative Ions. I. Negative Ions of Sulfur,
J. Chem. Phys., 1968, 48, 5, 2349, https://doi.org/10.1063/1.1669435
. [all data]
Thynne, 1972
Thynne, J.C.J.,
Negative Ion Studies with a Time-of-Flight Mass Spectrometer.,
Dyn. Mass Spectrom., 1972, 3, 67. [all data]
Bender, Carnovale, et al., 1988
Bender, H.; Carnovale, F.; Peel, J.B.; Wentrup, C.,
Dinitrogen sulfide, N2S, revealed by photoelectron spectroscopy,
J. Am. Chem. Soc., 1988, 110, 3458. [all data]
Liao and Ng, 1986
Liao, C.; Ng, C.,
Molecular beam photoionization study of S2,
J. Chem. Phys., 1986, 84, 788. [all data]
Rosinger, Grade, et al., 1983
Rosinger, W.; Grade, M.; Hirschwald, W.,
Detection of ion states of S2 to S8 by electron impact,
Int. J. Mass Spectrom. Ion Processes, 1983, 47, 239. [all data]
Grade, Wienecke, et al., 1983
Grade, M.; Wienecke, J.; Rosinger, W.; Hirschwald, W.,
Electron impact investigation of the molecules SeS(g) and TeSe(g) under high-temperature equilibrium conditions,
Ber. Bunsen-Ges. Phys. Chem., 1983, 87, 355. [all data]
Lau, Brittain, et al., 1982
Lau, K.H.; Brittain, R.D.; Hildenbrand, D.L.,
Vaporization of As2S3 and the dissociation energy of AsS,
J. Phys. Chem., 1982, 86, 4429. [all data]
Coppens, Reynaert, et al., 1979
Coppens, P.; Reynaert, J.C.; Drowart, J.,
Mass spectrometric study of the photoionization of carbon disulphide in the wavelength interval 125-60nm,
J. Chem. Soc. Faraday Trans. 2, 1979, 75, 292. [all data]
Tal'roze, Butkovskaya, et al., 1978
Tal'roze, V.L.; Butkovskaya, N.I.; Larichev, M.N.; Leipunskii, I.O.; Morozov, I.I.; Dodonov, A.F.; Kudrov, B.V.; Zelenov, V.V.; Raznikov, V.V.,
Advances in the mass spectrometry of free radicals,
Adv. Mass Spectrom., 1978, 7, 693. [all data]
Smoes, Drowart, et al., 1977
Smoes, S.; Drowart, J.; Welter, J.M.,
Thermodynamic study of the vaporization of europium monosulfide by Knudsen-cell mass spectrometry atomization energies of EuS(g), Eu2S(g), EuS2(g), Eu2O(g), Eu2O2(g), Eu2OS(g), and Eu2S2(g),
J. Chem. Thermodyn., 1977, 9, 275. [all data]
Piacente, Bardi, et al., 1976
Piacente, V.; Bardi, G.; di Paolo, V.; Ferro, D.,
The vapour pressure over Ga2S2 and Ga2Se2,
J. Chem. Thermodyn., 1976, 8, 391. [all data]
Hildenbrand, 1975
Hildenbrand, D.L.,
Vertical ionization potential of the CF2 radical,
Chem. Phys. Lett., 1975, 32, 30. [all data]
Golob, Jonathan, et al., 1975
Golob, L.; Jonathan, N.; Morris, A.; Okuda, M.; Ross, K.J.; Smith, D.J.,
Vacuum ultraviolet photoelectron spectroscopy of transient species,
J. Chem. Soc. Faraday Trans. 2, 1975, 71, 1026. [all data]
Berkowitz, 1975
Berkowitz, J.,
PES of high temperature vapors. VII. S2 and Te2,
J. Chem. Phys., 1975, 62, 4074. [all data]
Muenow and Margrave, 1972
Muenow, D.W.; Margrave, J.L.,
Mass spectrometric observations of gaseous phosphorus sulfides and oxysulfides,
J. Inorg. Nucl. Chem., 1972, 34, 89. [all data]
Hildenbrand, 1972
Hildenbrand, D.L.,
Thermochemistry of the molecules CS and CS+,
Chem. Phys. Lett., 1972, 15, 379. [all data]
Donovan, Husain, et al., 1970
Donovan, R.J.; Husain, D.; Stevenson, C.D.,
Vacuum ultra-violet spectra of transient molecules and radicals. Part 1. CS and S2,
J. Chem. Soc. Faraday Trans., 1970, 66, 1. [all data]
Barrow, duParcq, et al., 1969
Barrow, R.F.; duParcq, R.P.; Ricks, J.M.,
Rotational analysis of the C 3Σu--X 3g- system of 32S2,
J. Phys. B:, 1969, 2, 413. [all data]
Berkowitz and Lifshitz, 1968
Berkowitz, J.; Lifshitz, C.,
Photoionization of high temperature vapors. II. Sulfur molecular species,
J. Chem. Phys., 1968, 48, 4346. [all data]
Wu and Fehlner, 1976
Wu, M.; Fehlner, T.P.,
Valence level photoelectron spectra of some heavy group 4-6 diatomic molecules,
J. Am. Chem. Soc., 1976, 98, 7578. [all data]
Berkowitz and Chupka, 1969
Berkowitz, J.; Chupka, W.A.,
Photoionization of high-temperature vapors. VI. S2, Se2, and Te2,
J. Chem. Phys., 1969, 50, 4245. [all data]
Goodings, Bohme, et al., 1986
Goodings, J.M.; Bohme, D.K.; Elguindi, K.; Fox, A.,
Sulphur Anion Chemistry in Hydrocarbon Flames with H2S, OCS, and SO2 Additives,
Can. J. Chem., 1986, 64, 4, 689, https://doi.org/10.1139/v86-110
. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, References
- Symbols used in this document:
AE Appearance energy EA Electron affinity IE (evaluated) Recommended ionization energy ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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