1,3-Cyclopentadiene

• Formula: C₅H₆
• Molecular weight: 66.1011
• IUPAC Standard InChI: InChI=1S/C5H6/c1-2-4-5-3-1/h1-4H,5H2 Copy

  
• IUPAC Standard InChIKey: ZSWFCLXCOIISFI-UHFFFAOYSA-N Copy
• CAS Registry Number: 542-92-7
• 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.
• Other names: Cyclopentadiene; Pentole; Pyropentylene; R-Pentine
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Computational Chemistry Comparison and Benchmark Database
  • 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
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

Phase change data

Go To: Top, Gas phase thermochemistry 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Antoine Equation Parameters

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

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Enthalpy of fusion

Entropy of fusion

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.

Roth, Adamczak, et al., 1991
Roth, W.R.; Adamczak, O.; Breuckmann, R.; Lennartz, H.-W.; Boese, R., Die Berechnung von Resonanzenergien; das MM2ERW-Kraftfeld, Chem. Ber., 1991, 124, 2499-2521. [all data]

Furuyama, Golden, et al., 1970
Furuyama, S.; Golden, D.M.; Benson, S.W., Thermochemistry of cyclopentene and cyclopentadiene from studies of gas-phase equilibria, J. Chem. Thermodyn., 1970, 2, 161-169. [all data]

Wassermann, 1935
Wassermann, A., The mechanism of additions to double bonds. Part I. Thermochemistry and kinetics of a diene synthesis, J. Chem. Soc., 1935, 828-838. [all data]

Furuyama S., 1970
Furuyama S., Thermochemistry of cyclopentene and cyclopentadiene from studies of gas-phase equilibria, J. Chem. Thermodyn., 1970, 2, 161-169. [all data]

Grant C.J., 1969
Grant C.J., Reversibility in the gas-phase decomposition of cyclopentene. The entropy of cyclopentadiene, J. Chem. Soc. Chem. Comm., 1969, 667-668. [all data]

Dorofeeva O.V., 1986
Dorofeeva O.V., Thermodynamic properties of twenty-one monocyclic hydrocarbons, J. Phys. Chem. Ref. Data, 1986, 15, 437-464. [all data]

Turnbull A.G., 1967
Turnbull A.G., Thermochemistry of biscyclopentadienyl metal compounds, Austral. J. Chem., 1967, 20, 2059-2067. [all data]

Karni M., 1991
Karni M., Ab initio calculations and ideal gas thermodynamic functions of cyclopentadiene and cyclopentadiene derivatives, J. Phys. Chem. Ref. Data, 1991, 20, 665-683. [all data]

Murphy and Duggan, 1949
Murphy, M.T.; Duggan, A.C., Pyrolysis of Butadiene, J. Am. Chem. Soc., 1949, 71, 3347. [all data]

Staudinger, 1926
Staudinger, H., Ber. Dtsch. Chem. Ges., 1926, 59, 3019. [all data]

Lebedev and Lityagov, 1977
Lebedev, B.V.; Lityagov, V.Ya., Thermodynamics of polypentenamer synthesis reactions crystalline polytetrahydrofuran at 0 K, Vysokomol. Soedin., Ser. B, 1977, 19, 558. [all data]

Rogers, 1972
Rogers, F.E., Thermochemistry of the Diels-Alder reactions. II. Heat of addition of several dienes to tetracyanoethylene, J. Phys. Chem., 1972, 76, 106-109. [all data]

Hull, Reid, et al., 1965
Hull, H.S.; Reid, A.F.; Turnbull, A.G., Vapour pressures of cyclopentadiene and bis(cyclopentadienyl)magnesium, Aust. J. Chem., 1965, 18, 249. [all data]

Hull, Reid, et al., 1965, 2
Hull, HS; Reid, AF; Turnbull, AG, Vapour pressures of cyclopentadiene and Bis(cyclopentadienyl)magnesium, Aust. J. Chem., 1965, 18, 2, 249-621, https://doi.org/10.1071/CH9650249 . [all data]

Barrett and Burrage, 1932
Barrett, E.G.V.; Burrage, L.J., Some Observations on the Transformation of Cyclopentadiene into its Dimeride., J. Phys. Chem., 1932, 37, 8, 1029-1035, https://doi.org/10.1021/j150350a007 . [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]

Lesteva, Ogorodnikov, et al., 1967
Lesteva, T.M.; Ogorodnikov, S.K.; Morozova, A.I., Zh. Prikl. Khim. (Leningrad), 1967, 40, 4, 891. [all data]

Boublik, Fried, et al., 1984
Boublik, T.; Fried, V.; Hala, E., The Vapour Pressures of Pure Substances: Selected Values of the Temperature Dependence of the Vapour Pressures of Some Pure Substances in the Normal and Low Pressure Region, 2nd ed., Elsevier, New York, 1984, 972. [all data]

Lesteva, Ogoradnikov, et al., 1967
Lesteva, T.M.; Ogoradnikov, S.K.; Morozova, A., Kinetics of Dimerisation of Cyclopentadiene and Equilibrium of Liquid-Steam in System of Isoprene-Cyclopentadiene, Zh. Prikl. Khim. (Leningrad), 1967, 40, 891-894. [all data]

Lebedev and Lityagov, 1977, 2
Lebedev, B.V.; Lityagov, V.Ya., Thermodynamics of polypentenamer synthesis reactions, Vysokomol. Soedin., 1977, B19, 558-560. [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]

Notes

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

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  S°gas	Entropy of gas at standard conditions
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔcH°gas	Enthalpy of combustion of gas at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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