Phenylethyne

• Formula: C₈H₆
• Molecular weight: 102.1332
• IUPAC Standard InChI: InChI=1S/C8H6/c1-2-8-6-4-3-5-7-8/h1,3-7H Copy

  
• IUPAC Standard InChIKey: UEXCJVNBTNXOEH-UHFFFAOYSA-N Copy
• CAS Registry Number: 536-74-3
• 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.
• Isotopologues:
  • Benzene, beta-deuteroethynyl-
  • Benzene, beta-deuteroethynyl-
• Other names: Benzene, ethynyl-; Ethyne, phenyl-; Ethynylbenzene; Phenylacetylene; 1-Phenylethyne; Acetylene, phenyl-; Ethinylbenzene
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
  • NIST Polycyclic Aromatic Hydrocarbon Structure Index
• Options:
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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

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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

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
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Enthalpy of fusion

Entropy of fusion

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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

C₈H₅^- +  =

By formula: C₈H₅^- + H⁺ = C₈H₆

2 +  =

By formula: 2H₂ + C₈H₆ = C₈H₁₀

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:
B - John E. Bartmess
MM - Michael M. Meot-Ner (Mautner)
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to C₈H₆⁺ (ion structure unspecified)

Proton affinity at 298K

Gas basicity at 298K

Ionization energy determinations

De-protonation reactions

C₈H₅^- +  =

By formula: C₈H₅^- + H⁺ = C₈H₆

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• GAS (VAPOR PRESSURE OF LIQUID AT ROOM TEMPERATURE); Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution
• GAS (VAPOR PRESSURE OF LIQUID AT ROOM TEMPERATURE) $$ SEE SPECTRUM NO. 10136 FOR "SOLUTION" STATE $$ SEE SP. ACTA, VOL. 16, P. 918, 1960; Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 2 cm^-1 resolution
• SOLUTION (10% CCl4 FOR 2.5-7.5, 10% CS2 FOR 7.5-15 MICRON); Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution
• SOLUTION (10% IN CCl4 FOR 3800-1333, 10% IN CS2 FOR 1333-450 CM^-1); DOW KBr FOREPRISM-GRATING; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution

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

• gas

Gas Chromatography

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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

Kovats' RI, non-polar column, isothermal

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Kovats' RI, polar column, isothermal

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Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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Normal alkane RI, polar column, temperature ramp

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Normal alkane RI, polar column, custom temperature program

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Lee's RI, non-polar column, temperature ramp

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Lee's RI, non-polar column, custom temperature program

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References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Gas Chromatography, Notes

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

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Evans J.C., 1960
Evans J.C., The vibrational spectra ethynyl benzene and ethynyl benzene-d, Spectrochim. Acta, 1960, 16, 918-928. [all data]

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Moureu, C.; Andre, E., Thermochimie des composes acetyleniques, Ann. Chim. Phys., 1914, 1, 113-145. [all data]

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Lebedev, B.V.; Bykova, T.A.; Smirnova, N.N.; Kulagina, T.G., Thermodynmics of phenylacetylene, its cyclotrimerization, and the resulting 1,3,5-triphenylbenzene at 0-480 K, Zhur. Obshch. Khim., 1982, 52, 2630-2636. [all data]

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Flitcroft, T.L.; Skinner, H.A., Heats of hydrogenation Part 2.-Acetylene derivatives, Trans. Faraday Soc., 1958, 54, 47-53. [all data]

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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]

Aue, Guidoni, et al., 2000
Aue, D.H.; Guidoni, M.; Betowski, L.D., Ab initio calculated gas-phase basicities of polynuclear aromatic hydrocarbons, Int. J. Mass Spectrom., 2000, 201, 283. [all data]

Lichtenberger, Renshaw, et al., 1993
Lichtenberger, D.L.; Renshaw, S.K.; Bullock, R.M., Metal-acetylide bonding in (η<5>-C₅H₅)Fe(CO)₂C≡CR compounds. Measures of metal-dπ-acetylide-π interactions from photoelectron spectroscopy, J. Am. Chem. Soc., 1993, 115, 3276. [all data]

Dyke, Ozeki, et al., 1992
Dyke, J.M.; Ozeki, H.; Takahashi, M.; Cockett, M.C.R.; Kimura, K., A study of phenylacetylene and styrene, and their argon complexes PA-Ar and ST-Ar with laser threshold photoelectron spectroscopy, J. Chem. Phys., 1992, 97, 8926. [all data]

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Koppel, C.; Schwarz, H.; Bohlmann, F., Elektronenstossinduzierte fragmentierung von acetylenverbindungen, Org. Mass Spectrom., 1974, 9, 324. [all data]

Rabalais and Colton, 1973
Rabalais, J.W.; Colton, R.J., Electronic interaction between the phenyl group and its unsaturated substituents, J. Electron Spectrosc. Relat. Phenom., 1973, 1, 83. [all data]

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Palmer, M.H.; Moyes, W.; Spiers, M., The electronic structure of substituted benzenes: Ab initio calculations and photoelectron spectra for benzonitrile, the tolunitriles, fluorobenzonitriles, dicyanobenzenes and ethynylbenzene, J. Mol. Struct., 1980, 62, 165. [all data]

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Carlier, P.; Mouvier, G., Etude par spectrometrie de photoelectrons de la structure electronique des phenyl-alcynes conjugues, J. Electron Spectrosc. Relat. Phenom., 1979, 16, 169-181. [all data]

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Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Gas Chromatography, References

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  Cp,liquid	Constant pressure heat capacity of liquid
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  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
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization

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