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
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
  • 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)
  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
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Gas phase 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.

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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/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)

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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