2,4-Hexadiyne

• Formula: C₆H₆
• Molecular weight: 78.1118
• IUPAC Standard InChI: InChI=1S/C6H6/c1-3-5-6-4-2/h1-2H3 Copy

  
• IUPAC Standard InChIKey: PCTCNWZFDASPLA-UHFFFAOYSA-N Copy
• CAS Registry Number: 2809-69-0
• 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: Dimethylbutadiyne; Dimethyldiacetylene; CH3C≡CC≡CCH3; Hexa-2,4-diyne
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • IR Spectrum
  • Gas Chromatography
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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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Condensed 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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of solid

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:
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 sublimation

Enthalpy of phase transition

Entropy of phase transition

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 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
LL - Sharon G. Lias and Joel F. Liebman

View reactions leading to C₆H₆⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

Mass spectrum (electron ionization)

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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 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, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics 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.

Luk'yanova, Pimenova, et al., 1992
Luk'yanova, V.A.; Pimenova, S.M.; Timofeeva, L.P.; Kozina, M.P.; Kolesov, V.P.; Tarakanova, A.V., Standard enthalpies of formation of some derivatives of diacetylene, Russ. J. Phys. Chem. (Engl. Transl.), 1992, 66, 1083-1085. [all data]

Batley, Mraw, et al., 1982
Batley, M.; Mraw, S.; Staveley, L.A.K.; Overs, A.H.; Owen, M.C.; Thomas, R.K.; White, J.W., The structure and dynamics of crystalline 2,4-hexadiyne. I. Crystal structure, thermodynamics, and model calculations, Mol. Phys., 1982, 45(5), 1015-1034. [all data]

Farchan Laboratories, 1990
Farchan Laboratories, Research Chemicals Catalog, Farchan Laboratories, Gainesville, FL, 1990, 91. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Prevost, 1926
Prevost, C., The Catalytic Dehydrogenation of Vinylalcoylcarbinols, C. R. Hebd. Seances Acad. Sci., 1926, 183, 853. [all data]

Pauling, Springall, et al., 1939
Pauling, L.; Springall, H.D.; Palmer, K.J., The Electron Diffraction Investigation of Methylacetylene, Dimethyl- acetylene, Dimethyldiacetylene, Methyl Cyanide, Diacetylene and Cyanogen cyanogen, J. Am. Chem. Soc., 1939, 61, 927-8. [all data]

Meyer and Meyer, 1986
Meyer, E.F.; Meyer, J.J., Vapor Pressure of 2,4-Hexadiyne: Solid(0-21 deg C) and Liquid (91-135 deg C), J. Chem. Eng. Data, 1986, 31, 273. [all data]

Meyer and Meyer, 1986, 2
Meyer, Edwin F.; Meyer, John J., Vapor pressure of 2,4-hexadiyne: solid (0-21.degree.C) and liquid (91-135.degree.C), J. Chem. Eng. Data, 1986, 31, 3, 273-274, https://doi.org/10.1021/je00045a004 . [all data]

Rosenstock, McCulloh, et al., 1977
Rosenstock, H.M.; McCulloh, K.E.; Lossing, F.P., On the mechanisms of C₆H₆ ionization fragmentation, Int. J. Mass Spectrom. Ion Phys., 1977, 25, 327. [all data]

Heilbronner, Jones, et al., 1977
Heilbronner, E.; Jones, T.B.; Maier, J.P., 170. The ionization energies of di-n-alkyl diacetylenes, Helv. Chim. Acta, 1977, 60, 1697. [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]

Reeher, Flesch, et al., 1976
Reeher, J.R.; Flesch, G.D.; Svec, H.J., The mass spectra and ionization potentials of the neutral fragments produced during the electron bombardment of aromatic compounds, Org. Mass Spectrom., 1976, 11, 154. [all data]

Brogli, Heilbronner, et al., 1973
Brogli, F.; Heilbronner, E.; Hornung, V.; Kloster-Jensen, E., 230. Die photoelektronen-spektren methyl-substituierter Acetylene, Helv. Chim. Acta, 1973, 56, 2171. [all data]

Momigny, Brakier, et al., 1962
Momigny, J.; Brakier, L.; D'Or, L., Comparaison entre les effets de l'impact electronique sur le benzene et sur les isomeres du benzene en chaine ouverte, Bull. Classe Sci. Acad. Roy. Belg., 1962, 48, 1002. [all data]

Price and Walsh, 1945
Price, W.C.; Walsh, A.D., The absorption spectra of triple bond molecules in the vacuum ultra violet, J. Chem. Soc. Faraday Trans., 1945, 41, 381. [all data]

Bieri and Asbrink, 1980
Bieri, G.; Asbrink, L., 30.4-nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1980, 20, 149. [all data]

Dannacher, Stadelmann, et al., 1981
Dannacher, J.; Stadelmann, J.P.; Vogt, J., Competition between dissociative and nondissociative decay of excited perdeutero-2,4-hexadiyne cations, J. Chem. Phys., 1981, 74, 2094. [all data]

Dannacher, 1978
Dannacher, J., Photoelectron-photoion-coincidence measurements on 2,4-hexadiyne, Chem. Phys., 1978, 29, 339. [all data]

Kompe, Peel, et al., 1993
Kompe, B.; Peel, J.B.; Traeger, J.C., A theoretical and experimental study of the structures and stabilities of the [C₅H₃]⁺ cation, Org. Mass Spectrom., 1993, 28, 1253. [all data]

Ohmichi, Malinovich, et al., 1989
Ohmichi, N.; Malinovich, Y.; Ziesel, J.P.; Lifshitz, C., Time-dependent mass spectra and breakdown graphs. 12. Competitive dissociative isomerizations of the 2,4-hexadiyne cation, J. Phys. Chem., 1989, 93, 2491. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Cp,solid	Constant pressure heat capacity of solid
  S°solid,1 bar	Entropy of solid at standard conditions (1 bar)
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH°	Enthalpy of vaporization at standard conditions

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