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
• 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
  • Phase change data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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

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

Constant pressure heat capacity of liquid

Phase change 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Temperature of phase transition

Enthalpy of phase transition

Reaction 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C₆H₃F₂^- +  =

By formula: C₆H₃F₂^- + H⁺ = C₆H₄F₂

 +  = ( • )

By formula: H₄N⁺ + C₆H₄F₂ = (H₄N⁺ • C₆H₄F₂)

Free energy of reaction

 +  = ( • )

By formula: Cl^- + C₆H₄F₂ = (Cl^- • C₆H₄F₂)

C₆H₆⁺ +  = (C₆H₆⁺ • )

By formula: C₆H₆⁺ + C₆H₄F₂ = (C₆H₆⁺ • C₆H₄F₂)

Bond type: Charge transfer bond (positive ion)

C₆H₄F₂⁺ +  = (C₆H₄F₂⁺ • )

By formula: C₆H₄F₂⁺ + C₆H₄F₂ = (C₆H₄F₂⁺ • C₆H₄F₂)

Bond type: Charge transfer bond (positive ion)

 +  = ( • )

By formula: Cr⁺ + C₆H₄F₂ = (Cr⁺ • C₆H₄F₂)

IR Spectrum

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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

Gas Phase Spectrum

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Additional Data

Mass spectrum (electron ionization)

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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

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, 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, Lacina, et al., 1962
Good, W.D.; Lacina, J.L.; Scott, D.W.; McCullough, J.P., Combustion calorimetry of organic fluorine compounds. The heats of combustion and formation of the difluorobenzenes, 4-fluorotoluene and m-trifluorotoluic acid, J. Phys. Chem., 1962, 66, 1529-1532. [all data]

Swarts, 1919
Swarts, F., Etudes thermochimiques sur les combinaisons organiques fluorees, J. Chim. Phys., 1919, 17, 3-70. [all data]

Lichanot, 1991
Lichanot, A., Heat capacities of fluroaniline, fluorophenol and difluorobenzene in condensed phase, Thermochim. Acta, 1991, 177, 265-272. [all data]

PCR Inc., 1990
PCR Inc., Research Chemicals Catalog 1990-1991, PCR Inc., Gainesville, FL, 1990, 1. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Bergmann, Berkovic, et al., 1956
Bergmann, E.D.; Berkovic, S.; Ikan, R., A New Method for the Preparation of Aromatic Fluorine Compounds, J. Am. Chem. Soc., 1956, 78, 6037-9. [all data]

Goates, Ott, et al., 1976
Goates, J.R.; Ott, J.B.; Moellmer, J.F., Solid + Liquid Phase Equilibria and Solid-compound Formation in Halobenzenes + Aromatic Hydrocarbons, J. Chem. Thermodyn., 1976, 8, 217. [all data]

Osborn and Scott, 1980
Osborn, A.G.; Scott, D.W., Vapor pressures of 17 miscellanenous organic compounds, J. Chem. Thermodyn., 1980, 12, 429-438. [all data]

Basarová and Svoboda, 1991
Basarová, Pavlína; Svoboda, Václav, Calculation of heats of vaporization of halogenated hydrocarbons from saturated vapour pressure data, Fluid Phase Equilibria, 1991, 68, 13-34, https://doi.org/10.1016/0378-3812(91)85008-I . [all data]

Findlay, 1969
Findlay, T.J.V., Vapor pressures of fluorobenzenes from 5° to 50°C, J. Chem. Eng. Data, 1969, 14, 229. [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]

Deakyne and Meot-Ner (Mautner), 1985
Deakyne, C.A.; Meot-Ner (Mautner), M., Unconventional Ionic Hydrogen Bonds. 2. NH+ pi. Complexes of Onium Ions with Olefins and Benzene Derivatives, J. Am. Chem. Soc., 1985, 107, 2, 474, https://doi.org/10.1021/ja00288a034 . [all data]

Larson and McMahon, 1984
Larson, J.W.; McMahon, T.B., Hydrogen bonding in gas phase anions. An experimental investigation of the interaction between chloride ion and bronsted acids from ICR chloride exchange equilibria, J. Am. Chem. Soc., 1984, 106, 517. [all data]

Larson and McMahon, 1984, 2
Larson, J.W.; McMahon, T.B., Gas phase negative ion chemistry of alkylchloroformates, Can. J. Chem., 1984, 62, 675. [all data]

Ernstberger, Krause, et al., 1990
Ernstberger, B.; Krause, H.; Kiermeier, A.; Neusser, H.J., Multiphoton ionization and dissociation of mixed van der Waals clusters in a linear reflectron time-of-flight mass spectrometer, J. Chem. Phys., 1990, 92, 9, 5285, https://doi.org/10.1063/1.458603 . [all data]

Ryzhov, 1999
Ryzhov, V., Binding Energies of Chromium Cations with Fluorobenzenes from Radiative Association Kinetics, Int. J. Mass Spectrom., 1999, 185/186/187, 913. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  Cp,liquid	Constant pressure heat capacity of liquid
  T	Temperature
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttrs	Temperature of phase transition
  ΔHtrs	Enthalpy of phase transition
  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
  ΔrS°	Entropy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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