Cyclopentane

• Formula: C₅H₁₀
• Molecular weight: 70.1329
• IUPAC Standard InChI: InChI=1S/C5H10/c1-2-4-5-3-1/h1-5H2 Copy

  
• IUPAC Standard InChIKey: RGSFGYAAUTVSQA-UHFFFAOYSA-N Copy
• CAS Registry Number: 287-92-3
• 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.
• Other names: Pentamethylene; UN 1146
• 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
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • 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

Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics data, References, Notes

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
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

Constant pressure heat capacity of gas

Condensed phase thermochemistry data

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

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 liquid

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, References, Notes

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:
B - John E. Bartmess
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 C₅H₁₀⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₅H₉^- +  =

By formula: C₅H₉^- + H⁺ = C₅H₁₀

References

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

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

McCullough, Pennington, et al., 1959
McCullough, J.P.; Pennington, R.E.; Smith, J.C.; Hossenlopp, I.A.; Waddington, G., 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]

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]

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]

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]

Kilpatrick J.E., 1947
Kilpatrick J.E., The thermodynamics and molecular structure of cyclopentane, J. Am. Chem. Soc., 1947, 69, 2483-2488. [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]

Sundaram S., 1963
Sundaram S., Thermodynamic functions of some propellants, Z. Phys. Chem. (Frankfurt), 1963, 36, 376-377. [all data]

Spitzer R., 1946
Spitzer R., The heat capacity of gaseous cyclopentane, cyclohexane and methylcyclohexane, J. Am. Chem. Soc., 1946, 68, 2537-2538. [all data]

Kaarsemaker and Coops, 1952
Kaarsemaker, S.; Coops, J., Thermal quantities of some cycloparaffins. Part III. Results of measurements, Rec. Trav. Chim. Pays/Bas, 1952, 71, 261. [all data]

Douslin and Huffman, 1946
Douslin, D.R.; Huffman, H.M., The heat capacities, heats of transition, heats of fusion and entropies of cyclopentane, methylcyclopentane and methylcylohexane, J. Am. Chem. Soc., 1946, 68, 173-176. [all data]

Aston, Fink, et al., 1943
Aston, J.G.; Fink, H.L.; Schumann, S.C., The heat capacity and entropy, heats of transition, fusion and vaporization and the vapor pressures of cyclopentane. Evidence for a non-planar structure, J. Am. Chem. Soc., 1943, 65, 341-346. [all data]

Jacobs and Parks, 1934
Jacobs, C.J.; Parks, G.S., Thermal data on organic compounds. XIV. Some heat capacity, entropy and free energy data for cyclic substances, J. Am. Chem. Soc., 1934, 56, 1513-1517. [all data]

Tanaka, 1985
Tanaka, R., Excess heat capacities for mixtures of benzene with cyclopentane, methylcyclohexane, and cyclooctane at 298.15 K, J. Chem. Eng. Data, 1985, 30, 267-269. [all data]

Siddiqi, Svejda, et al., 1983
Siddiqi, M.A.; Svejda, P.; Kohler, F., A generalized van der Waals equation of state II. Excess heat capacities of mixtures containing cycloalkanes (C5,C6), methylcycloalkanes (C5,C6) and n-decane, Ber. Bunsenges. Phys. Chem., 1983, 87, 1176-1181. [all data]

Fortier, D'Arcy, et al., 1979
Fortier, J.-L.; D'Arcy, P.J.; Benson, G.C., Heat capacities of binary cycloalkane mixtures at 298.15 K, Thermochim. Acta, 1979, 28, 37-43. [all data]

Jolicoeur, Boileau, et al., 1975
Jolicoeur, C.; Boileau, J.; Bazinet, S.; Picker, P., Thermodynamic properties of aqueous organic solutes in relation to their structure. Part II. Apparent molal volumes and heat capacities of c-alkylamine hydrobromides in water, Can. J. Chem., 1975, 53, 716-722. [all data]

Szasz, Morrison, et al., 1947
Szasz, G.J.; Morrison, J.A.; Pace, E.L.; Aston, J.G., Thermal properties of cyclopentane and its use as a standard substance in low temperature thermal measurements, J. Chem. Phys., 1947, 15, 562-564. [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]

Traeger, 1986
Traeger, J.C., Heat of formation for the 1-methylallyl cation by photoionization mass spectrometry, J. Phys. Chem., 1986, 90, 4114. [all data]

Mautner(Meot-Ner), Sieck, et al., 1981
Mautner(Meot-Ner), M.; Sieck, L.W.; Ausloos, P., Ionization of normal alkanes: Enthalpy, entropy, structural, and isotope effects, J. Am. Chem. Soc., 1981, 103, 5342. [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]

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]

Puttemans, 1974
Puttemans, J.P., Ionisation de cycloalcanes (C₅ a C₁₂) en spectroscopie photoelectronique et par impact electronique, Ing. Chim. (Brussels), 1974, 56, 64. [all data]

Ikuta, Yoshihara, et al., 1973
Ikuta, S.; Yoshihara, K.; Shiokawa, T.; Jinno, M.; Yokoyama, Y.; Ikeda, S., Photoelectron spectroscopy of cyclohexane, cyclopentane, and some related compounds, Chem. Lett., 1973, 1237. [all data]

Lossing, 1972
Lossing, F.P., Free radicals by mass spectrometry. XLV. Ionization potentials and heats of formation of C₃H₃, C₃H₅, and C₄H₇ radicals and ions, Can. J. Chem., 1972, 50, 3973. [all data]

Gross and Wilkins, 1971
Gross, M.L.; Wilkins, C.L., Computer-assisted ion cyclotron resonance appearance potential measurements for C₅H₁₀ isomers, Anal. Chem., 1971, 43, 1624. [all data]

Praet and Delwiche, 1970
Praet, M.-T.; Delwiche, J., Ionization energies of some cyclic molecules, Chem. Phys. Lett., 1970, 5, 546. [all data]

Dewar and Worley, 1969
Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. I. Ionization potentials of some organic molecules and their interpretation, J. Chem. Phys., 1969, 50, 654. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [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]

Batich, Heilbronner, et al., 1974
Batich, C.; Heilbronner, E.; Rommel, E.; Semmelhack, M.F.; Foos, J.S., Equivalence of the energy gaps {DELTA}I(1,2) and {DELTA}E(1,2) between corresponding bands in the photoelectron (I) and electronic absorption (E) spectra of spiro[4.4]nonatetraene. An amusing consequence of spiroconjugation, J. Am. Chem. Soc., 1974, 96, 7662. [all data]

Brand and Baer, 1984
Brand, W.A.; Baer, T., Dissociation dynamics of energy-selected C₅H₁₀⁺ ions, J. Am. Chem. Soc., 1984, 106, 3154. [all data]

DePuy, Gronert, et al., 1989
DePuy, C.H.; Gronert, S.; Barlow, S.E.; Bierbaum, V.M.; Damrauer, R., The Gas Phase Acidities of the Alkanes, J. Am. Chem. Soc., 1989, 111, 6, 1968, https://doi.org/10.1021/ja00188a003 . [all data]

Peerboom, Rademaker, et al., 1992
Peerboom, R.A.L.; Rademaker, G.J.; Dekoning, L.J.; Nibbering, N.M.M., Stabilization of Cycloalkyl Carbanions in the Gas Phase, Rapid Commun. Mass Spectrom., 1992, 6, 6, 394, https://doi.org/10.1002/rcm.1290060608 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  S°liquid	Entropy of liquid at standard conditions
  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
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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