Heptane

• Formula: C₇H₁₆
• Molecular weight: 100.2019
• IUPAC Standard InChI: InChI=1S/C7H16/c1-3-5-7-6-4-2/h3-7H2,1-2H3 Copy

  
• IUPAC Standard InChIKey: IMNFDUFMRHMDMM-UHFFFAOYSA-N Copy
• CAS Registry Number: 142-82-5
• 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:
  • Heptane-1,2,3,4,5,6-d13
  • Heptane-1,2,3,4-d9
  • Heptane-1,2,3,-d7
  • Heptane-1-d3
  • Heptane-d16
• Other names: n-Heptane; Dipropylmethane; Heptyl hydride; Skellysolve C; n-C7H16; Eptani; Heptan; Heptanen; Gettysolve-C; NSC 62784
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Fluid Properties
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• 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
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

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
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

Ionization energy determinations

Appearance energy determinations

References

Go To: Top, Gas 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.

Prosen and Rossini, 1945
Prosen, E.J.; Rossini, F.D., Heats of combustion and formation of the paraffin hydrocarbons at 25° C, J. Res. NBS, 1945, 263-267. [all data]

Davies and Gilbert, 1941
Davies, G.F.; Gilbert, E.C., Heats of combustion and formation of the nine isomeric heptanes in the liquid state, J. Am. Chem. Soc., 1941, 63, 2730-2732. [all data]

Scott D.W., 1974
Scott D.W., Chemical Thermodynamic Properties of Hydrocarbons and Related Substances. Properties of the Alkane Hydrocarbons, C1 through C10 in the Ideal Gas State from 0 to 1500 K. U.S. Bureau of Mines, Bulletin 666, 1974. [all data]

Scott D.W., 1974, 2
Scott D.W., Correlation of the chemical thermodynamic properties of alkane hydrocarbons, J. Chem. Phys., 1974, 60, 3144-3165. [all data]

Pitzer K.S., 1944
Pitzer K.S., Thermodynamics of gaseous paraffins. Specific heat and related properties, Ind. Eng. Chem., 1944, 36, 829-831. [all data]

Pitzer K.S., 1946
Pitzer K.S., The entropies and related properties of branched paraffin hydrocarbons, Chem. Rev., 1946, 39, 435-447. [all data]

Waddington G., 1947
Waddington G., An improved flow calorimeter. Experimental vapor heat capacities and heats of vaporization of n-heptane and 2,2,3-trimethylbutane, J. Am. Chem. Soc., 1947, 69, 22-30. [all data]

Luo and Pacey, 1992
Luo, Y.-R.; Pacey, P.D., Effects of alkyl substitution on ionization energies of alkanes and haloalkanes and on heats of formation of their molecular cations. Part 2. Alkanes and chloro-, bromo- and iodoalkanes, Int. J. Mass Spectrom. Ion Processes, 1992, 112, 63. [all data]

Lias, 1982
Lias, S.G., Thermochemical information from ion-molecule rate constants, Ion Cyclotron Reson. Spectrom. 1982, 1982, 409. [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]

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]

Brehm, 1966
Brehm, B., Massenspektrometrische Untersuchung der Photoionisation von Molekulen, Z. Naturforsch., 1966, 21a, 196. [all data]

Turner and Al-Joboury, 1964
Turner, D.W.; Al-Joboury, M.I., Molecular photoelectron spectroscopy, Bull. Soc. Chim. Belges, 1964, 73, 428. [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]

Olmsted, Street, et al., 1964
Olmsted, J., III; Street, K., Jr.; Newton, A.S., Excess-kinetic-energy ions in organic mass spectra, J. Chem. Phys., 1964, 40, 2114. [all data]

Potzinger and Bunau, 1969
Potzinger, P.; Bunau, G.v., Empirische Beruksichtigung von Uberschussenergien bei der Auftrittspotentialbestimmung, Ber. Bunsen-Ges. Phys. Chem., 1969, 73, 466. [all data]

Steiner, Giese, et al., 1961
Steiner, B.; Giese, C.F.; Inghram, M.G., Photoionization of alkanes. Dissociation of excited molecular ions, J. Chem. Phys., 1961, 34, 189. [all data]

Lewis and Hamill, 1970
Lewis, D.; Hamill, W.H., Excited states of neutral molecular fragments from appearance potentials by electron impact in a mass spectrometer, J. Chem. Phys., 1970, 52, 6348. [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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