1,4-Cyclohexadiene

• Formula: C₆H₈
• Molecular weight: 80.1277
• IUPAC Standard InChI: InChI=1S/C6H8/c1-2-4-6-5-3-1/h1-2,5-6H,3-4H2 Copy

  
• IUPAC Standard InChIKey: UVJHQYIOXKWHFD-UHFFFAOYSA-N Copy
• CAS Registry Number: 628-41-1
• 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: 1,4-Dihydrobenzene; Cyclohexa-1,4-diene
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • 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.

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

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:
HL - Edward P. Hunter and Sharon G. Lias

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

View reactions leading to C₆H₈⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• LIQUID; Not specified, most likely a grating spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution
• LIQUID; Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution
• LIQUID (NEAT); CARY 90 (GRATING); DIGITIZED BY COBLENTZ SOCIETY (BATCH I) FROM HARD COPY; 2 cm^-1 resolution
• SOLUTION (10% CCl4 FOR 4000-1200, 10% CS2 FOR 1200-450) VS SOLVENT; CARY 90 (GRATING); DIGITIZED BY COBLENTZ SOCIETY (BATCH I) FROM HARD COPY

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas; HP-GC/MS/IRD

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Luk'yanova, Timofeeva, et al., 1991
Luk'yanova, V.A.; Timofeeva, L.P.; Kozina, M.P.; Kirin, V.N.; Tarakanova, A.V., Enthalpies of formation of certain unsaturated cyclic hydrocarbons, Russ. J. Phys. Chem. (Engl. Transl.), 1991, 65, 439-441. [all data]

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]

Steele, Chirico, et al., 1989
Steele, W.V.; Chirico, R.D.; Nguyen, A.; Hossenlopp, I.A.; Smith, N.K., Determination of some pure compound ideal-gas enthalpies of formation, AIChE Symp. Ser., 1989, 85, 140-162. [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]

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Bieri, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P., Valence ionization enrgies of hydrocarbons, Helv. Chim. Acta, 1977, 60, 2213. [all data]

Demeo and El-Sayed, 1970
Demeo, D.A.; El-Sayed, M.A., Ionization potential and structure of olefins, J. Chem. Phys., 1970, 52, 2622. [all data]

Franklin and Carroll, 1969
Franklin, J.L.; Carroll, S.R., Effect of molecular structure on ionic decomposition. II. An electron-impact study of 1,3-and 1,4-cyclohexadiene and 1,3,5-hexatriene, J. Am. Chem. Soc., 1969, 91, 6564. [all data]

Bischof, Hashmall, et al., 1969
Bischof, P.; Hashmall, J.A.; Heilbronner, E.; Hornung, V., Photoelektronspektroskopische Bestimmung der Wechselwirkung zwischen nichtkonjugierten Doppelbindungen, Helv. Chim. Acta, 1969, 52, 1745. [all data]

Bock and Kaim, 1980
Bock, H.; Kaim, W., Radical ions. 37. Ionization and one-electron oxidation of electron-rich silylalkyl olefins, J. Am. Chem. Soc., 1980, 102, 4429. [all data]

Kobayashi, 1978
Kobayashi, T., A new rule for photoelectron angular distributions of molecules, Phys. Lett. A, 1978, 69, 31. [all data]

Heilbronner, Brogli, et al., 1976
Heilbronner, E.; Brogli, F.; Vogel, E., Photoelectron spectroscopic assignment of symmetry to the ground state and first excited state of the 1,4-cyclohexadiene radical cation, J. Electron Spectrosc. Relat. Phenom., 1976, 9, 227. [all data]

Harrison, Haynes, et al., 1965
Harrison, A.G.; Haynes, P.; McLean, S.; Meyer, F., The mass spectra of methyl-substituted cyclopentadienes, J. Am. Chem. Soc., 1965, 87, 5099. [all data]

Lias and Ausloos, 1985
Lias, S.G.; Ausloos, P., Structures of C₆H₇⁺ ions formed in unimolecular and bimolecular reactions, J. Chem. Phys., 1985, 82, 3613. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

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