Disulfur monoxide

• Formula: OS₂
• Molecular weight: 80.129
• IUPAC Standard InChI: InChI=1S/OS2/c1-3-2 Copy

  
• IUPAC Standard InChIKey: TXKMVPPZCYKFAC-UHFFFAOYSA-N Copy
• CAS Registry Number: 20901-21-7
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • References
  • Notes
• Other data available:
  • Vibrational and/or electronic energy levels
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • 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
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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: F^- + OS₂ = (F^- • OS₂)

Gas phase ion energetics 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 evaluated as indicated in comments:
L - Sharon G. Lias

Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

Ion clustering data

Go To: Top, Gas phase thermochemistry data, 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
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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: F^- + OS₂ = (F^- • OS₂)

References

Go To: Top, Gas phase thermochemistry data, 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.

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Larson and McMahon, 1987
Larson, J.W.; McMahon, T.B., Trends in Gas Phase Fluoride Ion Affinities of the Main Group Oxyfluorides and Fluoride Sulfides. Fluoride Adducts of FAsO, FPO, FPO2, F2SiO, F4SO, FBO, F2SiS, FPS, FAsS, F2S2, and S2O., Inorg. Chem., 1987, 26, 24, 4018, https://doi.org/10.1021/ic00271a011 . [all data]

Wenthold and Squires, 1995
Wenthold, P.G.; Squires, R.R., Bond dissociation energies of F2(-) and HF2(-). A gas-phase experimental and G2 theoretical study, J. Phys. Chem., 1995, 99, 7, 2002, https://doi.org/10.1021/j100007a034 . [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]

Norwood and Ng, 1989
Norwood, K.; Ng, C.Y., Photoion-photoelectron coincidence spectroscopy of the transient molecules SO and S₂O, Chem. Phys. Lett., 1989, 156, 145. [all data]

Berkowitz, Eland, et al., 1977
Berkowitz, J.; Eland, J.H.D.; Appelman, E.H., Photoionization mass spectrometry and heat of formation of S₂O, J. Chem. Phys., 1977, 66, 2183. [all data]

Frost, Lee, et al., 1973
Frost, D.C.; Lee, S.T.; McDowell, C.A., The HeI photoelectron spectrum of S₂O, Chem. Phys. Lett., 1973, 22, 243. [all data]

Bock, Solouki, et al., 1973
Bock, H.; Solouki, B.; Rosmus, P.; Steudel, R., Photoelectron spectra and molecular properties: SSO and OSO, Angew. Chem. Int. Ed. Engl., 1973, 12, 933. [all data]

McDowell, 1972
McDowell, C.A., General disscussion, Faraday Discuss. Chem. Soc., 1972, 54, 68. [all data]

Hagemann, 1962
Hagemann, R., Determination de la chaleur de formation de S₂O par spectrometrie de masse, Compt. Rend., 1962, 255, 1102. [all data]

Rosmus, Dacre, et al., 1974
Rosmus, P.; Dacre, P.D.; Solouki, B.; Bock, H., Hartree-Fock calculations photoelectron spectra of SSO NSF, Theor. Chim. Acta, 1974, 35, 129. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, 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
  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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