1,2-Propadiene-1,3-dione

• Formula: C₃O₂
• Molecular weight: 68.0309
• IUPAC Standard InChI: InChI=1S/C3O2/c4-2-1-3-5 Copy

  
• IUPAC Standard InChIKey: GNEVIACKFGQMHB-UHFFFAOYSA-N Copy
• CAS Registry Number: 504-64-3
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: Carbon suboxide; Carbon oxide (C3O2); C3O2
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• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Gas phase ion energetics data
  • Vibrational and/or electronic energy levels
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Gas phase thermochemistry data

Go To: Top, Phase change data, Mass spectrum (electron ionization), 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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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Phase change 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:
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Phase change 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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), 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]

Kybett, Johnson, et al., 1965
Kybett, B.D.; Johnson, G.K.; Barker, C.K.; Margrave, J.L., The heats of formation and polymerization of carbon suboxide, J. Phys. Chem., 1965, 69, 3603-3606. [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

McDougall and Kilpatrick, 1965
McDougall, Lee A.; Kilpatrick, John E., Entropy and Related Thermodynamic Properties of Carbon Suboxide, J. Chem. Phys., 1965, 42, 7, 2311, https://doi.org/10.1063/1.1696294 . [all data]

McDougall and Kilpatrick, 1965, 2
McDougall, L.A.; Kilpatrick, J.E., Entropy and Related Thermodynamic Properties of Carbon Suboxide, J. Chem. Phys., 1965, 42, 7, 2311-2321, https://doi.org/10.1063/1.1696294 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), 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
  ΔvapH	Enthalpy of vaporization

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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