Neopentane

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Gas phase thermochemistry data

Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), 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
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas-167.9 ± 0.63kJ/molCcbGood, 1970ALS
Δfgas-168.5 ± 1.0kJ/molCmPilcher and Chadwick, 1967ALS
Δfgas-166.0 ± 1.0kJ/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Δcgas-3514.1 ± 0.96kJ/molCmPilcher and Chadwick, 1967Corresponding Δfgas = -168.5 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
120.82 ± 0.25298.15Hossenlopp I.A., 1981GT
129.58 ± 0.26323.15
138.41 ± 0.28348.15
147.06 ± 0.29373.15
155.46 ± 0.31398.15
163.52 ± 0.32423.15
171.46 ± 0.34448.15
178.95 ± 0.36473.15
186.42 ± 0.37498.15
193.38 ± 0.39523.15

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
80.54200.Scott D.W., 1974Recommended values were obtained from the consistent correlation scheme for alkanes [ Scott D.W., 1974, 2, Scott D.W., 1974]. This approach gives a better agreement with experimental data than the statistical thermodynamics calculation [ Pitzer K.S., 1946].; GT
111.63273.15
120.83 ± 0.25298.15
121.55300.
155.98400.
186.98500.
214.64600.
238.91700.
261.08800.
280.33900.
297.901000.
313.381100.
327.191200.
338.901300.
351.461400.
359.821500.

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Mass spectrum (electron ionization), 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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Quantity Value Units Method Reference Comment
IE (evaluated)≤10.30 ± 0.08eVN/AN/AL

Ionization energy determinations

IE (eV) Method Reference Comment
10.21 ± 0.04PEJonas, Schweitzer, et al., 1973LLK
10.3 ± 0.1PEEvans, Green, et al., 1972LLK
10.40PEDewar and Worley, 1969RDSH
10.35PIWatanabe, Nakayama, et al., 1962RDSH
10.90PEKimura, Katsumata, et al., 1981Vertical value; LLK
10.9 ± 0.1PEBieri, Burger, et al., 1977Vertical value; LLK
11.3PESchmidt and Wilkins, 1972Vertical value; LLK
11.3PEMurrell and Schmidt, 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH3+29.5 ± 0.2?EIOlmsted, Street, et al., 1964RDSH
CH3+13.14?EILampe and Field, 1959RDSH
C2H3+17.95?EILampe and Field, 1959RDSH
C2H5+13.81?EILampe and Field, 1959RDSH
C3H3+17.08?EILampe and Field, 1959RDSH
C3H5+13.13?EILampe and Field, 1959RDSH
C4H8+10.39 ± 0.02CH4PISteiner, Giese, et al., 1961RDSH
C4H9+10.35CH3PIChesnavich, Su, et al., 1978LLK
C4H9+10.56CH3EILossing and Semeluk, 1970RDSH
C4H9+10.57 ± 0.02CH3PISteiner, Giese, et al., 1961RDSH

De-protonation reactions

C5H11- + Hydrogen cation = Neopentane

By formula: C5H11- + H+ = C5H12

Quantity Value Units Method Reference Comment
Δr1711. ± 8.4kJ/molBranDePuy, Gronert, et al., 1989gas phase; B
Δr1720. ± 42.kJ/molCIDTGraul and Squires, 1990gas phase; B
Quantity Value Units Method Reference Comment
Δr1674. ± 8.8kJ/molH-TSDePuy, Gronert, et al., 1989gas phase; B

Mass spectrum (electron ionization)

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

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NIST MS number 280

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References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), Notes

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

Good, 1970
Good, W.D., The enthalpies of combustion and formation of the isomeric pentanes, J. Chem. Thermodyn., 1970, 2, 237-244. [all data]

Pilcher and Chadwick, 1967
Pilcher, G.; Chadwick, J.D.M., Measurements of heats of combustion by flame calorimetry. Part 4.-n-Pentane, isopentane, neopentane, Trans. Faraday Soc., 1967, 63, 2357-2361. [all data]

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]

Hossenlopp I.A., 1981
Hossenlopp I.A., Vapor heat capacities and enthalpies of vaporization of five alkane hydrocarbons, J. Chem. Thermodyn., 1981, 13, 415-421. [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., 1946
Pitzer K.S., The entropies and related properties of branched paraffin hydrocarbons, Chem. Rev., 1946, 39, 435-447. [all data]

Jonas, Schweitzer, et al., 1973
Jonas, A.E.; Schweitzer, G.K.; Grimm, F.A.; Carlson, T.A., The photoelectron spectra of the tetrafluoro and tetramethyl compounds of the group IV elements, J. Electron Spectrosc. Relat. Phenom., 1973, 1, 29. [all data]

Evans, Green, et al., 1972
Evans, S.; Green, J.C.; Joachim, P.J.; Orchard, A.F.; Turner, D.W.; Maier, J.P., Electronic structures of the Group IVB tetramethyls by helium-(I) photoelectron spectroscopy, J. Chem. Soc. Faraday Trans. 2, 1972, 68, 905. [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]

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]

Schmidt and Wilkins, 1972
Schmidt, W.; Wilkins, B.T., Das "Equivalent Orbital" (EO)-verfahren zur interpretation von photoelektronen(PE)-spektren: Neopentan, Angew. Chem., 1972, 84, 168. [all data]

Murrell and Schmidt, 1972
Murrell, J.N.; Schmidt, W., Photoelectron spectroscopic correlation of the molecular orbitals of methane, ethane, propane, isobutane and neopentane, J. Chem. Soc. Faraday Trans. 2, 1972, 68, 1709. [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]

Lampe and Field, 1959
Lampe, F.W.; Field, F.H., The decomposition of neopentane under electron impact, J. Am. Chem. Soc., 1959, 81, 3238. [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]

Chesnavich, Su, et al., 1978
Chesnavich, W.J.; Su, T.; Bowers, M.T., Reactions of vibrationally excited ions. A theoretical and experimental analysis of the reaction (C4H9+) + NH3 Ü NH4+ + C4H8, J. Am. Chem. Soc., 1978, 100, 4362. [all data]

Lossing and Semeluk, 1970
Lossing, F.P.; Semeluk, G.P., Free radicals by mass spectrometry. XLII.Ionization potentials and ionic heats of formation for C1-C4 alkyl radicals, Can. J. Chem., 1970, 48, 955. [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]

Graul and Squires, 1990
Graul, S.T.; Squires, R.R., Gas-Phase Acidities Derived from Threshold Energies for Activated Reactions, J. Am. Chem. Soc., 1990, 112, 7, 2517, https://doi.org/10.1021/ja00163a007 . [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), References