Benzene, 1,4-difluoro-

• Formula: C₆H₄F₂
• Molecular weight: 114.0928
• IUPAC Standard InChI: InChI=1S/C6H4F2/c7-5-1-2-6(8)4-3-5/h1-4H Copy

  
• IUPAC Standard InChIKey: QUGUFLJIAFISSW-UHFFFAOYSA-N Copy
• CAS Registry Number: 540-36-3
• 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: Benzene, p-difluoro-; p-Difluorobenzene; 1,4-Difluorobenzene; para-Difluorobenzene
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• Information on this page:
  • Gas phase ion energetics data
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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

Appearance energy determinations

De-protonation reactions

C₆H₃F₂^- +  =

By formula: C₆H₃F₂^- + H⁺ = C₆H₄F₂

Gas Chromatography

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

Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, temperature ramp

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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.

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Rieger, Reiser, et al., 1992
Rieger, D.; Reiser, G.; Muller-Dethlefs, K.; Schlag, E.W., Zero kinetic energy photoelectron spectroscopy of p-difluorobenzene, J. Phys. Chem., 1992, 96, 12. [all data]

Reiger, 1990
Reiger, D., [Title unavailable], Diplomarbeit, Techn. Universitat Munich, 1990. [all data]

Bieri, Asbrink, et al., 1981
Bieri, G.; Asbrink, L.; Von Niessen, W., 30.4 nm He(II) photoelectron spectra of organic molecules. Part IV. Fluoro-compounds (C,H,F), J. Electron Spectrosc. Relat. Phenom., 1981, 23, 281. [all data]

Lias and Ausloos, 1978
Lias, S.G.; Ausloos, P.J., eIonization energies of organic compounds by equilibrium measurements, J. Am. Chem. Soc., 1978, 100, 6027. [all data]

Gilbert and Sandorfy, 1974
Gilbert, R.; Sandorfy, C., Rydberg transitions in the ultraviolet spectra of difluorobenzenes, Chem. Phys. Lett., 1974, 27, 457. [all data]

Clark and Frost, 1967
Clark, I.D.; Frost, D.C., A study of the energy levels in benzene and some fluorobenzenes by photoelectron spectroscopy, J. Am. Chem. Soc., 1967, 89, 244. [all data]

Bralsford, Harris, et al., 1960
Bralsford, R.; Harris, P.V.; Price, W.C., The effect of fluorine on the electronic spectra and ionization potentials of molecules, Proc. Roy. Soc. (London), 1960, A258, 459. [all data]

Sell, Mintz, et al., 1978
Sell, J.A.; Mintz, D.M.; Kupperman, A., Photoelectron angular distributions of carbon-carbon π electrons in ethylene, benzene, and their fluorinated derivatives, Chem. Phys. Lett., 1978, 58, 601. [all data]

Streets and Ceasar, 1973
Streets, D.G.; Ceasar, G.P., Inductive mesomeric effects on the π orbitals of halobenzenes, Mol. Phys., 1973, 26, 1037. [all data]

Klessinger, 1972
Klessinger, M., Ionization potentials of substituted benzenes, Angew. Chem. Int. Ed. Engl., 1972, 11, 525. [all data]

Momigny and Wirtz-Cordier, 1962
Momigny, J.; Wirtz-Cordier, A.M., Les effets de l'impact electronique sur des derives dihalogenes du benzene, Ann. Soc. Sci. Bruxelles, 1962, 76, 164. [all data]

Majer and Patrick, 1962
Majer, J.R.; Patrick, C.R., Electron impact on some halogenated aromatic compounds, J. Chem. Soc. Faraday Trans., 1962, 58, 17. [all data]

Buker, Nibbering, et al., 1997
Buker, H.H.; Nibbering, N.M.M.; Espinosa, D.; Mongin, F.; Schlosser, M., Additivity of substituent effects in the fluoroarene series: Equilibrium acidity in the gas phase and deprotonation rates in ethereal solution, Tetrahed. Lett., 1997, 38, 49, 8519-8522, https://doi.org/10.1016/S0040-4039(97)10303-3 . [all data]

Briscese and Riveros, 1975
Briscese, S.M.J.; Riveros, J.M., Gas phase nucleophilic reactions of aromatic systems, J. Am. Chem. Soc., 1975, 97, 230. [all data]

Peng, Ding, et al., 1988
Peng, C.T.; Ding, S.F.; Hua, R.L.; Yang, Z.C., Prediction of Retention Indexes I. Structure-Retention Index Relationship on Apolar Columns, J. Chromatogr., 1988, 436, 137-172, https://doi.org/10.1016/S0021-9673(00)94575-8 . [all data]

Zenkevich, 2005
Zenkevich, I.G., Experimentally measured retention indices., 2005. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  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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