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Difluoromethane

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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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Deltafgas-107.71kcal/molReviewChase, 1998Data last reviewed in December, 1969
Deltafgas-108.08 ± 0.22kcal/molCcrNeugebauer and Margrave, 1958Corrected for CODATA value of «DELTA»fH; ALS
Quantity Value Units Method Reference Comment
Deltacgas-139.36kcal/molCcrNeugebauer and Margrave, 1958Corrected for CODATA value of «DELTA»fH; ALS
Quantity Value Units Method Reference Comment
gas,1 bar58.963cal/mol*KReviewChase, 1998Data last reviewed in December, 1969

Gas Phase Heat Capacity (Shomate Equation)

Cp° = A + B*t + C*t2 + D*t3 + E/t2
H° − H°298.15= A*t + B*t2/2 + C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 − E/(2*t2) + G
    Cp = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Temperature (K) 298. - 1200.1200. - 6000.
A -1.45762022.62800
B 42.834611.669091
C -29.24670-0.320721
D 7.7203810.021364
E 0.117438-4.318980
F -108.5430-124.1750
G 46.3188173.39250
H -107.7100-107.7100
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in December, 1969 Data last reviewed in December, 1969

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry 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 as indicated in comments:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
MS - José A. Martinho Simões
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

CHF2- + Hydrogen cation = Difluoromethane

By formula: CHF2- + H+ = CH2F2

Quantity Value Units Method Reference Comment
Deltar389.0 ± 3.5kcal/molCIDTGraul and Squires, 1990gas phase; G2 calculations( Lee, Dyke, et al., 1998) predict «DELTA»Hacid = 399 kcal/mol; B
Quantity Value Units Method Reference Comment
Deltar381.2 ± 3.6kcal/molH-TSGraul and Squires, 1990gas phase; G2 calculations( Lee, Dyke, et al., 1998) predict «DELTA»Hacid = 399 kcal/mol; B
Deltar379.0 ± 6.0kcal/molIMRBSullivan, 1977gas phase; B

Lithium ion (1+) + Difluoromethane = (Lithium ion (1+) bullet Difluoromethane)

By formula: Li+ + CH2F2 = (Li+ bullet CH2F2)

Quantity Value Units Method Reference Comment
Deltar26.5kcal/molICRStaley and Beauchamp, 1975gas phase; switching reaction(Li+)H2O, from graph; Dzidic and Kebarle, 1970 interpolated; M

C5O5W (g) + Difluoromethane (g) = C6H2F2O5W (g)

By formula: C5O5W (g) + CH2F2 (g) = C6H2F2O5W (g)

Quantity Value Units Method Reference Comment
Deltar>-5.00kcal/molEqGBrown, Ishikawa, et al., 1990Temperature range: ca. 300-350 K; MS

Difluoromethane + Bromine = Hydrogen bromide + Methane, bromodifluoro-

By formula: CH2F2 + Br2 = HBr + CHBrF2

Quantity Value Units Method Reference Comment
Deltar-9.54 ± 0.07kcal/molEqkOkafo and Whittle, 1974gas phase; ALS

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Notes

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

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Neugebauer and Margrave, 1958
Neugebauer, C.A.; Margrave, J.L., The heats of formation of CHF3 and CH2F2, J. Phys. Chem., 1958, 62, 1043-1048. [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]

Lee, Dyke, et al., 1998
Lee, E.P.F.; Dyke, J.M.; Mayhew, C.A., Study of the OH-+CH2F2 reaction by selected ion flow tube experiments and ab initio calculations, J. Phys. Chem. A, 1998, 102, 43, 8349-8354, https://doi.org/10.1021/jp982224y . [all data]

Sullivan, 1977
Sullivan, S.A., Thesis, Cal. Inst. Tech. thesis,, 1977. [all data]

Staley and Beauchamp, 1975
Staley, R.H.; Beauchamp, J.L., Intrinsic Acid - Base Properties of Molecules. Binding Energies of Li+ to pi - and n - Donor Bases, J. Am. Chem. Soc., 1975, 97, 20, 5920, https://doi.org/10.1021/ja00853a050 . [all data]

Dzidic and Kebarle, 1970
Dzidic, I.; Kebarle, P., Hydration of the Alkali Ions in the Gas Phase. Enthalpies and Entropies of Reactions M+(H2O)n-1 + H2O = M+(H2O)n, J. Phys. Chem., 1970, 74, 7, 1466, https://doi.org/10.1021/j100702a013 . [all data]

Brown, Ishikawa, et al., 1990
Brown, C.E.; Ishikawa, Y.; Hackett, P.A.; Rayner, D.M., J. Am. Chem. Soc., 1990, 112, 2530. [all data]

Okafo and Whittle, 1974
Okafo, E.N.; Whittle, E., Bond dissociation energies from equilibrium studies. Part 5.-The equilibria Br2 + CH2F2 = HBr + CHF2Br and Br2 + CH3F = HBr + CH2FBr. Determination of D(CHF2-Br) and «DELTA»H°f (CHF2Br,g), Trans. Faraday Soc., 1974, 17, 1366-1375. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, References