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.
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• 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)
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

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.

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.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

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

(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
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.