Sulfur dimer

• Formula: S₂
• Molecular weight: 64.130
• IUPAC Standard InChI: InChI=1S/S2/c1-2 Copy

  
• IUPAC Standard InChIKey: MAHNFPMIPQKPPI-UHFFFAOYSA-N Copy
• CAS Registry Number: 23550-45-0
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
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• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Ion clustering data
  • Constants of diatomic molecules
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Gas Phase Kinetics Database
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Gas phase thermochemistry 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.

Gas Phase Heat Capacity (Shomate Equation)

C_p° = 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
    C_p = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Reaction thermochemistry data

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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

(HS₂^- • 4294967295) +  = HS₂^-

By formula: (HS₂^- • 4294967295S₂) + S₂ = HS₂^-

(OS₂^- • 4294967295) +  = OS₂^-

By formula: (OS₂^- • 4294967295S₂) + S₂ = OS₂^-

( • ) +  = ( • 2)

By formula: (V⁺ • S₂) + S₂ = (V⁺ • 2S₂)

( • ) +  = ( • 2)

By formula: (Mo⁺ • S₂) + S₂ = (Mo⁺ • 2S₂)

 +  = ( • )

By formula: V⁺ + S₂ = (V⁺ • S₂)

 +  = ( • )

By formula: Mo⁺ + S₂ = (Mo⁺ • S₂)

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, 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.

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)

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

Anion protonation reactions

S₂^- +  = HS₂

By formula: S₂^- + H⁺ = HS₂

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics 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]

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 3Σ_u--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, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  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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