Cyclooctane

• Formula: C₈H₁₆
• Molecular weight: 112.2126
• IUPAC Standard InChI: InChI=1S/C8H16/c1-2-4-6-8-7-5-3-1/h1-8H2 Copy

  
• IUPAC Standard InChIKey: WJTCGQSWYFHTAC-UHFFFAOYSA-N Copy
• CAS Registry Number: 292-64-8
• 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: Octamethylene
• 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
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
• Data at other public NIST sites:
  • 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:
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
BS - Robert L. Brown and Stephen E. Stein
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

Reduced pressure boiling point

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 sublimation

Enthalpy of fusion

Enthalpy of phase transition

Entropy of phase transition

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 by: 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

 +  =

By formula: H₂ + C₈H₁₄ = C₈H₁₆

 +  =

By formula: H₂ + C₈H₁₄ = C₈H₁₆

3 +  =

By formula: 3H₂ + C₈H₁₀ = C₈H₁₆

2 +  =

By formula: 2H₂ + C₈H₁₂ = C₈H₁₆

 + 2 =

By formula: C₈H₁₂ + 2H₂ = C₈H₁₆

2 +  =

By formula: 2H₂ + C₈H₁₂ = C₈H₁₆

 + 2 =

By formula: C₈H₁₂ + 2H₂ = C₈H₁₆

3 +  =

By formula: 3H₂ + C₈H₁₀ = C₈H₁₆

4 +  =

By formula: 4H₂ + C₈H₈ = C₈H₁₆

4 +  =

By formula: 4H₂ + C₈H₈ = C₈H₁₆

 +  =

By formula: H₂ + C₈H₁₄ = C₈H₁₆

2 +  =

By formula: 2H₂ + C₈H₁₂ = C₈H₁₆

2 +  =

By formula: 2H₂ + C₈H₁₂ = C₈H₁₆

2 +  =

By formula: 2H₂ + C₈H₁₂ = C₈H₁₆

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• LIQUID; Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution
• SOLUTION (10% CCl4 FOR 4000-1330, 10% CS2 FOR 1330-450 CM^-1) VS SOLVENT; CARY 90 (GRATING); 2 cm^-1 resolution

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

• gas

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

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, non-polar column, temperature ramp

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

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

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Van Den Dool and Kratz RI, 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, custom temperature program

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References

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, Notes

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

Spitzer and Huffman, 1947
Spitzer, R.; Huffman, H.M., The heats of combustion of cyclopentane, cyclohexane, cycloheptane and cyclooctane, J. Am. Chem. Soc., 1947, 69, 211-213. [all data]

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Finke H.L., Cycloheptane, cyclooctane, and 1,3,5-cycloheptatriene. Low-temperature thermal properties, vapor pressure, and derived chemical thermodynamic properties, J. Am. Chem. Soc., 1956, 78, 5469-5476. [all data]

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Finke, Scott, et al., 1956
Finke, H.L.; Scott, D.W.; Gross, M.E.; Messerly, J.F.; Waddington, G., Cycloheptane, Cyclooctane and 1,3,5-Cycloheptatriene. Low Temperature Thermal Properties, Vapor Pressure and Derived Chemical Thermodynamic Prop., J. Am. Chem. Soc., 1956, 78, 5469. [all data]

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Daubert, 1996
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Young, 1972
Young, C.L., Gas-liquid critical properties of the cycloalkanes and their mixtures, Aust. J. Chem., 1972, 25, 1625-30. [all data]

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Hicks, C.P.; Young, C.L., Critical Temperatures of Mixtures of Quasi-spherical Molecules. Alicyclic Hydrocarbons + Benzene, + Hexafluorobenzene and + Perfluorocyclohexane, Trans. Faraday Soc., 1971, 67, 1605-11. [all data]

Finke, Scott, et al., 1956, 2
Finke, H.L.; Scott, D.W.; Gross, M.E.; Messerly, J.F.; Waddington, G., Cycloheptane, cyclooctane and 1,3,5-cycloheptatriene. Low temperature thermal properties, vapor pressure and derived chemical thermodynamic properties, J. Am. Chem. Soc., 1956, 78, 5469-54. [all data]

Finke, Scott, et al., 1956, 3
Finke, H.L.; Scott, D.W.; Gross, M.E.; Messerly, J.F.; Waddington, G., Cycloheptane, cyclooctane and 1,3,5-cycloheptatriene. Low temperature thermal properties, vapor pressure and derived chemical thermodynamic properties, J. Am. Chem. Soc., 1956, 78, 5469-5476. [all data]

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Wu, Locke, et al., 1991
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Meyer, Edwin F.; Hotz, Carol A., Cohesive energies in polar organic liquids. 3. Cyclic ketones, J. Chem. Eng. Data, 1976, 21, 3, 274-279, https://doi.org/10.1021/je60070a035 . [all data]

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Anand, Subhash C.; Grolier, Jean P.E.; Kiyohara, Osamu; Halpin, Carl J.; Benson, George C., Thermodynamic properties of some cycloalkane-cycloalkanol systems at 298. 15K. III, J. Chem. Eng. Data, 1975, 20, 2, 184-189, https://doi.org/10.1021/je60065a020 . [all data]

Bondi, 1963
Bondi, A., Heat of Siblimation of Molecular Crystals: A Catalog of Molecular Structure Increments., J. Chem. Eng. Data, 1963, 8, 3, 371-381, https://doi.org/10.1021/je60018a027 . [all data]

Acree, 1991
Acree, William E., Thermodynamic properties of organic compounds: enthalpy of fusion and melting point temperature compilation, Thermochimica Acta, 1991, 189, 1, 37-56, https://doi.org/10.1016/0040-6031(91)87098-H . [all data]

Doering, Roth, et al., 1989
Doering, W.E.; Roth, W.R.; Bauer, F.; Breuckmann, R.; Ebbrecht, T.; Herbold, M.; Schmidt, R.; Lennartz, H-W.; Lenoir, D.; Boese, R., Rotational barriers of strained olefines, Chem. Ber., 1989, 122, 1263-1266. [all data]

Roth and Lennartz, 1980
Roth, W.R.; Lennartz, H.W., Heats of hydrogenation. I. Determination of heats of hydrogenation with an isothermal titration calorimeter, Chem. Ber., 1980, 113, 1806-1817. [all data]

Rogers, Von Voithenberg, et al., 1978
Rogers, D.W.; Von Voithenberg, H.; Allinger, N.L., Heats of hydrogenation of the cis and trans isomers of cyclooctene, J. Org. Chem., 1978, 43, 360-361. [all data]

Turner and Meador, 1957
Turner, R.B.; Meador, W.R., Heats of hydrogenation. IV. Hydrogenation of some cis- and trans-cycloolefins, J. Am. Chem. Soc., 1957, 79, 4133-4136. [all data]

Conn, Kistiakowsky, et al., 1939
Conn, J.B.; Kistiakowsky, G.B.; Smith, E.A., Heats of organic reactions. VIII. Some further hydrogenations, including those of some acetylenes, J. Am. Chem. Soc., 1939, 61, 1868-1876. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [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]

Turner, Mallon, et al., 1973
Turner, R.B.; Mallon, B.J.; Tichy, M.; Doering, W.v.E.; Roth, W.R.; Schroder, G., Heats of hydrogenation. X. Conjugative interaction in cyclic dienes and trienes, J. Am. Chem. Soc., 1973, 95, 8605-8610. [all data]

Turner, Meador, et al., 1957
Turner, R.B.; Meador, W.R.; Doering, W.E.; Knox, L.H.; Mayer, J.R.; Wiley, D.W., Heats of hydrogenation. III. Hydrogenation of cycllooctatetraene and of some seven-membered non-benzenoid aromatic compounds, J. Am. Chem. Soc., 1957, 79, 4127-4133. [all data]

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Roth, W.R.; Hopf, H.; Horn, C., Propargyl-Stabilisierungsenergie, Chem. Ber., 1994, 127, 1781-1795. [all data]

Turner, Jarrett, et al., 1973
Turner, R.B.; Jarrett, A.D.; Goebel, P.; Mallon, B.J., Heats of hydrogenation. 9. Cyclic acetylenes and some miscellaneous olefins, J. Am. Chem. Soc., 1973, 95, 790-792. [all data]

Rogers and McLafferty, 1971
Rogers, D.W.; McLafferty, F.J., A new hydrogen calorimeter. Heats of hydrogenation of allyl and vinyl unsaturation adjacent to a ring, Tetrahedron, 1971, 27, 3765-3775. [all data]

Dallos, Sisak, et al., 2000
Dallos, A.; Sisak, A.; Kulcsár, Z.; Kováts, E., Pair-wise interactions by gas chromatography VII. Interaction free enthalpies of solutes with secondary alcohol groups, J. Chromatogr. A, 2000, 904, 2, 211-242, https://doi.org/10.1016/S0021-9673(00)00908-0 . [all data]

Reddy, Dutoit, et al., 1992
Reddy, K.S.; Dutoit, J.-Cl.; Kovats, E. sz., Pair-wise interactions by gas chromatography. I. Interaction free enthalpies of solutes with non-associated primary alcohol groups, J. Chromatogr., 1992, 609, 1-2, 229-259, https://doi.org/10.1016/0021-9673(92)80167-S . [all data]

Zhang, Li, et al., 1992
Zhang, M.J.; Li, S.D.; Chen, B.J., Compositional studies of high-temperature coal tar by GC/FTIR analysis of light oil fractions, Chromatographia, 1992, 33, 3/4, 138-146, https://doi.org/10.1007/BF02275894 . [all data]

Dutoit, 1991
Dutoit, J., Gas chromatographic retention behaviour of some solutes on structurally similar polar and non-polar stationary phases, J. Chromatogr., 1991, 555, 1-2, 191-204, https://doi.org/10.1016/S0021-9673(01)87179-X . [all data]

Engewald, Billing, et al., 1987
Engewald, W.; Billing, U.; Welsch, T.; Haufe, G., Structure-retention correlations of hydrocarbons in gas-liquid and gas-solid chromatography. Cycloalkenes and cycloalkadienes, Chromatographia, 1987, 23, 8, 590-594, https://doi.org/10.1007/BF02324870 . [all data]

Bredael, 1982
Bredael, P., Retention indices of hydrocarbons on SE-30, J. Hi. Res. Chromatogr. Chromatogr. Comm., 1982, 5, 6, 325-328, https://doi.org/10.1002/jhrc.1240050610 . [all data]

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Agrawal, B.B.; Tesarík, K.; Janák, J., Gas chromatographic characterization of sulphur compounds in the 93-162° gasoline cut from Romashkino crude oil using Kováts retention indices, J. Chromatogr., 1972, 65, 1, 207-215, https://doi.org/10.1016/S0021-9673(00)86933-2 . [all data]

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Hively, R.A.; Hinton, R.E., Variation of the retention index with temperature on squalane substrates, J. Gas Chromatogr., 1968, 6, 4, 203-217, https://doi.org/10.1093/chromsci/6.4.203 . [all data]

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Schomburg, G., Struktur und Retentionsverhalten von Offenkettigen und Cyclischen Kohlenwasserstoffen und Deren Einfacher Substitutionsprodukte, Anal. Chim. Acta., 1967, 38, 45-64, https://doi.org/10.1016/S0003-2670(01)80560-2 . [all data]

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Chen, H.-F., Quantitative prediction of gas chromatography retention indices with support vector machines, radial basis neutral networks and multiple linear regression, Anal. Chim. Acta, 2008, 609, 1, 24-36, https://doi.org/10.1016/j.aca.2008.01.003 . [all data]

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Robinson, P.G.; Odell, A.L., A system of standard retention indices and its uses. The characterisation of stationary phases and the prediction of retention indices, J. Chromatogr., 1971, 57, 1-10, https://doi.org/10.1016/0021-9673(71)80001-8 . [all data]

Robinson and Odell, 1971, 2
Robinson, P.G.; Odell, A.L., Comparison of isothermal and non-linear temperature programmed gas chromatography. The temperature dependence of the retention indices of a number of hydrocarbons on squalane and SE-30, J. Chromatogr., 1971, 57, 11-17, https://doi.org/10.1016/0021-9673(71)80002-X . [all data]

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Peng, C.T.; Yang, Z.C.; Ding, S.F., Prediction of rentention idexes. II. Structure-retention index relationship on polar columns, J. Chromatogr., 1991, 586, 1, 85-112, https://doi.org/10.1016/0021-9673(91)80028-F . [all data]

Notes

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

• Symbols used in this document:
  

  Cp,gas	Constant pressure heat capacity of gas
  Pc	Critical pressure
  S°gas	Entropy of gas at standard conditions
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  Vc	Critical volume
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions
  ρc	Critical density

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