Cyclopentane, methyl-

• Formula: C₆H₁₂
• Molecular weight: 84.1595
• IUPAC Standard InChI: InChI=1S/C6H12/c1-6-4-2-3-5-6/h6H,2-5H2,1H3 Copy

  
• IUPAC Standard InChIKey: GDOPTJXRTPNYNR-UHFFFAOYSA-N Copy
• CAS Registry Number: 96-37-7
• 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: Methylcyclopentane; UN 2298
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• 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
  • Henry's Law 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:
DRB - Donald R. Burgess, Jr.
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

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:
L - Sharon G. Lias

Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
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 C₆H₁₂⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• LIQUID (NEAT); PERKIN-ELMER 180 (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

References

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

Good and Smith, 1969
Good, W.D.; Smith, N.K., Enthalpies of combustion of toluene, benzene, cyclohexane, cyclohexene, methylcyclopentane, 1-methylcyclopentene, and n-hexane, J. Chem. Eng. Data, 1969, 14, 102-106. [all data]

Prosen, Johnson, et al., 1946
Prosen, E.J.; Johnson, W.H.; Rossini, F.D., Heats of formation and combustion of the normal alkylcyclopentanes and cyclohexanes and the increment per CH₂ group for several homologous series of hydrocarbons, J. Res. NBS, 1946, 37, 51-56. [all data]

Moore, Renquist, et al., 1940
Moore, G.E.; Renquist, M.L.; Parks, G.S., Thermal data on organic compounds. XX. Modern combustion data for two methylnonanes, methyl ethyl ketone, thiophene and six cycloparaffins, J. Am. Chem. Soc., 1940, 62, 1505-1507. [all data]

Thermodynamics Research Center, 1997
Thermodynamics Research Center, Selected Values of Properties of Chemical Compounds., Thermodynamics Research Center, Texas A&M University, College Station, Texas, 1997. [all data]

Scott D.W., 1960
Scott D.W., Chemical thermodynamic properties of methylcyclopentane and 1-cis-3-dimethylcyclopentane, J. Phys. Chem., 1960, 64, 906-908. [all data]

McCullough J.P., 1959
McCullough J.P., Thermodynamics of cyclopentane, methylcyclopentane and 1,cis-3-dimethylcyclopentane: verification of the concept of pseudorotation, J. Am. Chem. Soc., 1959, 81, 5880-5883. [all data]

Holmes and Lossing, 1991
Holmes, J.L.; Lossing, F.P., Ionization energies of homologous organic compounds and correlation with molecular size, Org. Mass Spectrom., 1991, 26, 537. [all data]

Lias, Ausloos, et al., 1976
Lias, S.G.; Ausloos, P.; Horvath, Z., Charge transfer reactions in alkane and cycloalkane systems. Estimated ionization potentials, Int. J. Chem. Kinet., 1976, 8, 725. [all data]

Lossing and Traeger, 1975
Lossing, F.P.; Traeger, J.C., Stabilization in cyclopentadienyl, cyclopentenyl, and cyclopentyl cations, J. Am. Chem. Soc., 1975, 97, 1579. [all data]

Rang, Paldoia, et al., 1974
Rang, S.; Paldoia, P.; Talvari, A., Ionization potentials of unsaturated hydrocarbons. 2. Mono-substituted cyclopentenes and cyclohexenes, Eesti. NSV Tead. Akad. Toim., 1974, 354. [all data]

Pottie, Harrison, et al., 1961
Pottie, R.F.; Harrison, A.G.; Lossing, F.P., Free radicals by mass spectrometry. XXIV. Ionization potentials of cycloalkyl free radicals and cycloalkanes, J. Am. Chem. Soc., 1961, 83, 3204. [all data]

Lossing and Traeger, 1975, 2
Lossing, F.P.; Traeger, J.C., Free radicals by mass spectrometry XLVI. Heats of formation of C₅H₇ and C₅H₉ radicals and cations., J. Am. Chem. Soc., 1975, 19, 9. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  IE (evaluated)	Recommended ionization energy
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

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