2,4-Hexadiene, 2,5-dimethyl-

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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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Δfgas-4.59 ± 0.20kcal/molCcrSteele, Chirico, et al., 1990 

Condensed 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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Δfliquid-15.09 ± 0.20kcal/molCcrSteele, Chirico, et al., 1990ALS
Quantity Value Units Method Reference Comment
Δcliquid-1215.53 ± 0.17kcal/molCcrSteele, Chirico, et al., 1990Corresponding Δfliquid = -15.09 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
109.7298.15Steele, Chirico, et al., 1990Authors give Cp/R = 55.2. This value appears too large by a factor of two. Actual Cp should be around 229.5 J/mol*K.; DH

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 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

Ionization energy determinations

IE (eV) Method Reference Comment
7.67PEMasclet, Mouvier, et al., 1981LLK
7.65PEBeez, Bieri, et al., 1973LLK
7.91 ± 0.04EIFranklin and Mogenis, 1967RDSH
7.67PEWerstiuk, Clark, et al., 1990Vertical value; LL

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C3H3+26.5 ± 0.1?EIFranklin and Mogenis, 1967RDSH
C3H5+14.27 ± 0.03?EIFranklin and Mogenis, 1967RDSH
C3H7+12.23 ± 0.06?EIFranklin and Mogenis, 1967RDSH
C4H5+14.60 ± 0.04?EIFranklin and Mogenis, 1967RDSH
C4H7+13.03 ± 0.02?EIFranklin and Mogenis, 1967RDSH
C5H7+12.88 ± 0.03C2H4+CH3EIFranklin and Mogenis, 1967RDSH
C6H5+16.1 ± 0.1?EIFranklin and Mogenis, 1967RDSH
C6H7+14.42 ± 0.05?EIFranklin and Mogenis, 1967RDSH
C6H9+11.7 ± 0.1?EIFranklin and Mogenis, 1967RDSH
C7H11+10.80 ± 0.03CH3EIFranklin and Mogenis, 1967RDSH

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.

Steele, Chirico, et al., 1990
Steele, W.V.; Chirico, R.D.; Nguyen, A.; Hossenlopp, I.A.; Smith, N.K., Determination of ideal-gas enthalpies of formation for key compounds, Am. Inst. Chem. Eng. Symp. Ser. (AIChE Symp. Ser.), 1990, 138-154. [all data]

Masclet, Mouvier, et al., 1981
Masclet, P.; Mouvier, G.; Bocquet, J.F., Effets electroniques et effets steriques dus a la substitution alcoyle dans les dienes conjugues, J. Chim. Phys., 1981, 78, 99. [all data]

Beez, Bieri, et al., 1973
Beez, M.; Bieri, G.; Bock, H.; Heilbronner, E., The ionization potentials of butadiene, hexatriene, andtheir methyl derivatives: evidence for through space interaction between double bond π-orbitals and non-bonded pseudo-π orbitals of methyl groups?, Helv. Chim. Acta, 1973, 56, 1028. [all data]

Franklin and Mogenis, 1967
Franklin, J.L.; Mogenis, A., An electron impact study of ions from several dienes, J. Phys. Chem., 1967, 71, 2820. [all data]

Werstiuk, Clark, et al., 1990
Werstiuk, N.H.; Clark, K.B.; Leigh, W.J., Conformational analysis and structure elucidation of 2,3-dimethyl and 2,4-dimethyl-2,4-hexadienes by AM1 and He(I) ultraviolet photoelectron spectroscopy, Can. J. Chem., 1990, 68, 2078. [all data]


Notes

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