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Benzene, 1,2-difluoro-

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Deltafgas-283.0 ± 0.92kJ/molCcrGood, Lacina, et al., 1962Corrected for CODATA value of «DELTA»fH

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
Deltafliquid-319.2 ± 0.92kJ/molCcrGood, Lacina, et al., 1962Corrected for CODATA value of «DELTA»fH; ALS
Quantity Value Units Method Reference Comment
Deltacliquid-2960.7 ± 0.54kJ/molCcrGood, Lacina, et al., 1962Corrected for CODATA value of «DELTA»fH; ALS
Quantity Value Units Method Reference Comment
liquid222.59J/mol*KN/AScott, Messerly, et al., 1963DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
159.03298.15Scott, Messerly, et al., 1963T = 14 to 357 K.; DH
159.4298.15Good, Lacina, et al., 1962DH

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

Quantity Value Units Method Reference Comment
Tboil365.2KN/AAldrich Chemical Company Inc., 1990BS
Tboil364. - 365.KN/APCR Inc., 1990BS
Tboil367.1KN/AMajer and Svoboda, 1985 
Quantity Value Units Method Reference Comment
Ttriple226.010KN/AScott, Messerly, et al., 1963, 2Uncertainty assigned by TRC = 0.01 K; TRC
Quantity Value Units Method Reference Comment
Tc557.3KN/AMajer and Svoboda, 1985 
Quantity Value Units Method Reference Comment
Deltavap36.24kJ/molN/AMajer and Svoboda, 1985 
Deltavap36.2kJ/molN/ABoublik, Fried, et al., 1984Based on data from 300. - 400. K. See also Basarová and Svoboda, 1991.; AC
Deltavap36.2kJ/molVScott, Messerly, et al., 1963, 3hfusion=2.64kcal/mol; ALS
Deltavap36.2 ± 0.08kJ/molVGood, Lacina, et al., 1962Corrected for CODATA value of «DELTA»fH; ALS

Reduced pressure boiling point

Tboil (K) Pressure (bar) Reference Comment
364.71.00Weast and Grasselli, 1989BS

Enthalpy of vaporization

DeltavapH (kJ/mol) Temperature (K) Method Reference Comment
32.21367.1N/AMajer and Svoboda, 1985 
35.5319.EBScott, Messerly, et al., 1963, 3Based on data from 304. - 403. K. See also Boublik, Fried, et al., 1984.; AC
34.6 ± 0.1327.CScott, Messerly, et al., 1963, 3AC
33.5 ± 0.1345.CScott, Messerly, et al., 1963, 3AC
32.2 ± 0.1367.CScott, Messerly, et al., 1963, 3AC

Enthalpy of vaporization

ΔvapH = A exp(-βTr) (1 − Tr)β
    ΔvapH = Enthalpy of vaporization (at saturation pressure) (kJ/mol)
    Tr = reduced temperature (T / Tc)

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Temperature (K) A (kJ/mol) beta Tc (K) Reference Comment
298. - 367.51.350.2691557.3Majer and Svoboda, 1985 

Antoine Equation Parameters

log10(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Temperature (K) A B C Reference Comment
304.31 - 403.404.145211310.271-50.563Scott, Messerly, et al., 1963Coefficents calculated by NIST from author's data.

Enthalpy of fusion

DeltafusH (kJ/mol) Temperature (K) Reference Comment
11.046226.01Scott, Messerly, et al., 1963DH
11.05226.Domalski and Hearing, 1996AC

Entropy of fusion

DeltafusS (J/mol*K) Temperature (K) Reference Comment
48.87226.01Scott, Messerly, et al., 1963DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, 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:
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- + Hydrogen cation = Benzene, 1,2-difluoro-

By formula: C6H3F2- + H+ = C6H4F2

Quantity Value Units Method Reference Comment
Deltar1580. ± 9.2kJ/molG+TSBuker, Nibbering, et al., 1997gas phase; B
Deltar1582. ± 13.kJ/molG+TSBriscese and Riveros, 1975gas phase; Between EtO-, iPrO-; value altered from reference due to change in acidity scale; B
Quantity Value Units Method Reference Comment
Deltar1546. ± 8.4kJ/molIMREBuker, Nibbering, et al., 1997gas phase; B
Deltar1547. ± 13.kJ/molIMRBBriscese and Riveros, 1975gas phase; Between EtO-, iPrO-; value altered from reference due to change in acidity scale; B

C6H6+ + Benzene, 1,2-difluoro- = (C6H6+ bullet Benzene, 1,2-difluoro-)

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

Bond type: Charge transfer bond (positive ion)

Quantity Value Units Method Reference Comment
Deltar63.6kJ/molPHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Deltar110.J/mol*KN/AMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M

Free energy of reaction

DeltarG° (kJ/mol) T (K) Method Reference Comment
26.330.PHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M

Chlorine anion + Benzene, 1,2-difluoro- = (Chlorine anion bullet Benzene, 1,2-difluoro-)

By formula: Cl- + C6H4F2 = (Cl- bullet C6H4F2)

Quantity Value Units Method Reference Comment
Deltar59.8 ± 8.4kJ/molIMRELarson and McMahon, 1984gas phase; B,M
Quantity Value Units Method Reference Comment
Deltar90.4J/mol*KN/ALarson and McMahon, 1984gas phase; switching reaction(Cl-)ClCOOCH3, Entropy change calculated or estimated; Larson and McMahon, 1984, 2; M
Quantity Value Units Method Reference Comment
Deltar33. ± 8.4kJ/molIMRELarson and McMahon, 1984gas phase; B,M

Chromium ion (1+) + Benzene, 1,2-difluoro- = (Chromium ion (1+) bullet Benzene, 1,2-difluoro-)

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

Quantity Value Units Method Reference Comment
Deltar138.kJ/molRAKRyzhov, 1999RCD

Henry's Law data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, 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 by: Rolf Sander

Henry's Law constant (water solution)

kH(T) = H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
H = Henry's law constant for solubility in water at 298.15 K (mol/kg*bar)
d(ln(kH))/d(1/T) = Temperature dependence constant (K)

H (mol/kg*bar) d(ln(kH))/d(1/T) (K) Method Reference Comment
0.14 QN/A missing citation give several references for the Henry's law constants but don't assign them to specific species.

Gas phase ion energetics data

Go To: Top, 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), 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:
HL - Edward P. Hunter and Sharon G. Lias
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)9.29 ± 0.01eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)731.2kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity703.5kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.284 ± 0.008EQLias and Ausloos, 1978LLK
9.30SGilbert and Sandorfy, 1974LLK
9.74 ± 0.02EIMomigny and Wirtz-Cordier, 1962RDSH
9.31PIBralsford, Harris, et al., 1960RDSH
9.30PEStreets and Ceasar, 1973Vertical value; LLK
9.6 ± 0.03PEKlessinger, 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C4H2F2+15.27C2H2EIMomigny and Wirtz-Cordier, 1962RDSH

De-protonation reactions

C6H3F2- + Hydrogen cation = Benzene, 1,2-difluoro-

By formula: C6H3F2- + H+ = C6H4F2

Quantity Value Units Method Reference Comment
Deltar1580. ± 9.2kJ/molG+TSBuker, Nibbering, et al., 1997gas phase; B
Deltar1582. ± 13.kJ/molG+TSBriscese and Riveros, 1975gas phase; Between EtO-, iPrO-; value altered from reference due to change in acidity scale; B
Quantity Value Units Method Reference Comment
Deltar1546. ± 8.4kJ/molIMREBuker, Nibbering, et al., 1997gas phase; B
Deltar1547. ± 13.kJ/molIMRBBriscese and Riveros, 1975gas phase; Between EtO-, iPrO-; value altered from reference due to change in acidity scale; B

Ion clustering data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, 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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

C6H6+ + Benzene, 1,2-difluoro- = (C6H6+ bullet Benzene, 1,2-difluoro-)

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

Bond type: Charge transfer bond (positive ion)

Quantity Value Units Method Reference Comment
Deltar63.6kJ/molPHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Deltar110.J/mol*KN/AMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M

Free energy of reaction

DeltarG° (kJ/mol) T (K) Method Reference Comment
26.330.PHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M

Chlorine anion + Benzene, 1,2-difluoro- = (Chlorine anion bullet Benzene, 1,2-difluoro-)

By formula: Cl- + C6H4F2 = (Cl- bullet C6H4F2)

Quantity Value Units Method Reference Comment
Deltar59.8 ± 8.4kJ/molIMRELarson and McMahon, 1984gas phase; B,M
Quantity Value Units Method Reference Comment
Deltar90.4J/mol*KN/ALarson and McMahon, 1984gas phase; switching reaction(Cl-)ClCOOCH3, Entropy change calculated or estimated; Larson and McMahon, 1984, 2; M
Quantity Value Units Method Reference Comment
Deltar33. ± 8.4kJ/molIMRELarson and McMahon, 1984gas phase; B,M

Chromium ion (1+) + Benzene, 1,2-difluoro- = (Chromium ion (1+) bullet Benzene, 1,2-difluoro-)

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

Quantity Value Units Method Reference Comment
Deltar138.kJ/molRAKRyzhov, 1999RCD

IR Spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), References, Notes

Data compiled by: Coblentz Society, Inc.

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


Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, 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

Spectrum

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Additional Data

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin Japan AIST/NIMC Database- Spectrum MS-NW-9256
NIST MS number 230727

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References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Ion clustering 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]

Scott, Messerly, et al., 1963
Scott, D.W.; Messerly, J.F.; Todd, S.S.; Hossenlopp, I.A.; Osborn, A.; McCullough, J.P., 1,2-Difluorobenzene: Chemical thermodynamic properties and vibrational assignment, J. Chem. Phys., 1963, 38, 532-539. [all data]

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]

PCR Inc., 1990
PCR Inc., Research Chemicals Catalog 1990-1991, PCR Inc., Gainesville, FL, 1990, 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]

Scott, Messerly, et al., 1963, 2
Scott, D.W.; Messerly, J.F.; Todd, S.S.; Hossenlopp, I.A.; Osborn, A.G.; McCullough, J.P., 1,2-difluorobenzene: chemical thermodynamic properties and vibrational assignment, J. Chem. Phys., 1963, 38, 532-9. [all data]

Boublik, Fried, et al., 1984
Boublik, T.; Fried, V.; Hala, E., The Vapour Pressures of Pure Substances: Selected Values of the Temperature Dependence of the Vapour Pressures of Some Pure Substances in the Normal and Low Pressure Region, 2nd ed., Elsevier, New York, 1984, 972. [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]

Scott, Messerly, et al., 1963, 3
Scott, D.W.; Messerly, J.F.; Todd, S.S.; Hossenlopp, I.A.; Osborn, A.; McCullough, J.P., 1,2-Difluorobenzene: Chemical thermodynamic properties and vibrationnal assignment, J. Chem. Phys., 1963, 38, 532. [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]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [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]

Meot-Ner (Mautner), Hamlet, et al., 1978
Meot-Ner (Mautner), M.; Hamlet, P.; Hunter, E.P.; Field, F.H., Bonding Energies in Association Ions of Aromatic Molecules. Correlations with Ionization Energies, J. Am. Chem. Soc., 1978, 100, 17, 5466, https://doi.org/10.1021/ja00485a034 . [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]

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]

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]

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]

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]

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]

Streets and Ceasar, 1973
Streets, D.G.; Ceasar, G.P., Inductive mesomeric effects on the «pi» 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]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), References