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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

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

Quantity Value Units Method Reference Comment
Tboil221.4KN/APCR Inc., 1990BS
Tboil221.KN/AFilatov, Makarov, et al., 1968Uncertainty assigned by TRC = 2. K; TRC
Tboil221.6KN/ACroll and Scott, 1964Uncertainty assigned by TRC = 0.3 K; TRC
Tboil221.6KN/AHenne, Renoll, et al., 1939Uncertainty assigned by TRC = 1. K; TRC
Quantity Value Units Method Reference Comment
Tc351.3 ± 0.1KAVGN/AAverage of 6 values; Individual data points
Quantity Value Units Method Reference Comment
Pc57.09atmN/AShi, Zhu, et al., 1998Uncertainty assigned by TRC = 0.03 atm; by extrapolation of vapor pressure to Tc; TRC
Pc57.09atmN/AFu, Han, et al., 1995Uncertainty assigned by TRC = 0.04 atm; TRC
Pc57.09atmN/AHigashi, 1994Uncertainty assigned by TRC = 0.09 atm; TRC
Pc57.084atmN/ASato, Sato, et al., 1994Uncertainty assigned by TRC = 0.025 atm; TRC
Quantity Value Units Method Reference Comment
rhoc8.2 ± 0.1mol/lAVGN/AAverage of 7 values; Individual data points

Enthalpy of vaporization

DeltavapH (kcal/mol) Temperature (K) Method Reference Comment
4.92230.N/AKanungo, Oi, et al., 1987Based on data from 149. - 245. K.; AC
4.76271.AStephenson and Malanowski, 1987Based on data from 256. - 321. K.; AC
5.07207.AStephenson and Malanowski, 1987Based on data from 191. - 222. K.; AC
4.85243.AStephenson and Malanowski, 1987Based on data from 191. - 258. K.; AC
4.85331.AStephenson and Malanowski, 1987Based on data from 316. - 351. K.; AC
5.07206.N/AMalbrunot, Meunier, et al., 1968Based on data from 191. - 221. K.; AC
4.92227.N/AMalbrunot, Meunier, et al., 1968Based on data from 191. - 242. K.; AC

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
191.19 - 241.334.25653821.092-28.554Malbrunot, Meunier, et al., 1968Coefficents calculated by NIST from author's data.

Enthalpy of fusion

DeltafusH (kcal/mol) Temperature (K) Reference Comment
1.04136.4L«65533»ddecke and Magee, 1996AC

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

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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
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

Henry's Law 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: 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
0.086 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

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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
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)12.71eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)148.3kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity140.9kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
12.70PEPullen, Carlson, et al., 1970RDSH
12.72PEBrundle, Robin, et al., 1970RDSH
13.27EIHarshbarger, Robin, et al., 1973Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CF+18.8?EILifshitz and Long, 1965RDSH
CF2+14.8 ± 0.4H2EISteele, 1964RDSH
CHF+17.7?EILifshitz and Long, 1965RDSH
CHF2+13.11HEILossing, 1972LLK
CHF2+13.14 ± 0.02HEIMartin, Lampe, et al., 1966RDSH
CHF2+13.1HEILifshitz and Long, 1965RDSH
CH2F+14.06FEILossing, 1972LLK
CH2F+15.28FEILifshitz and Long, 1965RDSH

De-protonation 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

Ion clustering data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, Site Links, NIST Free Links, 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: Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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

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

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

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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.
NIST MS number 90

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Gas Chromatography

Go To: Top, Gas 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), Site Links, NIST Free Links, 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

Normal alkane RI, non-polar column, temperature ramp

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Column type Active phase I Reference Comment
CapillaryOV-101230.Zenkevich, 200525. m/0.20 mm/0.10 «mu»m, N2/He, 6. K/min; Tstart: 50. C; Tend: 250. C

Normal alkane RI, non-polar column, custom temperature program

View large format table.

Column type Active phase I Reference Comment
CapillaryPorapack Q183.Zenkevich and Rodin, 2004Program: not specified

References

Go To: Top, Gas 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), Gas Chromatography, Site Links, NIST Free Links, 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]

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

Filatov, Makarov, et al., 1968
Filatov, A.S.; Makarov, S.P.; Yakubovich, A.Ya., Halogenation of 1,1,1-Trifluoroazomethane, Zh. Obshch. Khim., 1968, 38, 33. [all data]

Croll and Scott, 1964
Croll, I.M.; Scott, R.L., Fluorocarbon Solutions at Low Termperatures IV. The Liquid Mixtures CH4 + CClF3, CH2F2 + CClF3, CHF3 + CClF3, CF4 + CClF3, C2H6 + CClF3, C2H6 + CF4, and CHF3 + CF4, J. Phys. Chem., 1964, 68, 3853. [all data]

Henne, Renoll, et al., 1939
Henne, A.L.; Renoll, M.W.; Leicester, H.M., J. Am. Chem. Soc., 1939, 61, 938. [all data]

Shi, Zhu, et al., 1998
Shi, L.; Zhu, M.; Han, L.; Duan, Y.; Sun, L.; Fu, Y.-D., Thermophysical Properties of Difluoromethane (HFC-32), Science in China, Ser. E, 1998, 41, 435-42. [all data]

Fu, Han, et al., 1995
Fu, Y.D.; Han, L.-Z.; Zhu, M.-S., PVT properties, vapor pressures and critical parameters of HFC-32, Fluid Phase Equilib., 1995, 111, 273-86. [all data]

Higashi, 1994
Higashi, Y., Critical parameters for HFC134a, HFC32 and HFC125, Int. J. Refrig., 1994, 17, 524-531. [all data]

Sato, Sato, et al., 1994
Sato, T.; Sato, H.; Watanabe, K., PVT Property Measurements for Difluoromethane, J. Chem. Eng. Data, 1994, 39, 851-4. [all data]

Kanungo, Oi, et al., 1987
Kanungo, Arundhati.; Oi, Takao.; Popowicz, Anthony.; Ishida, Takanobu., Vapor pressure isotope effects in liquid methylene difluoride, J. Phys. Chem., 1987, 91, 15, 4198-4203, https://doi.org/10.1021/j100299a049 . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Malbrunot, Meunier, et al., 1968
Malbrunot, P.F.; Meunier, P.A.; Scatena, Georges M.; Mears, Whitney H.; Murphy, Kevin Paul.; Sinka, Joseph V., Pressure-volume-temperature behavior of difluoromethane, J. Chem. Eng. Data, 1968, 13, 1, 16-21, https://doi.org/10.1021/je60036a006 . [all data]

L«65533»ddecke and Magee, 1996
L«65533»ddecke, T.O.; Magee, J.W., Molar heat capacity at constant volume of difluoromethane (R32) and pentafluoroethane (R125) from the triple-point temperature to 345 K at pressures to 35 MPa, Int J Thermophys, 1996, 17, 4, 823-849, https://doi.org/10.1007/BF01439192 . [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]

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]

Pullen, Carlson, et al., 1970
Pullen, B.P.; Carlson, T.A.; Moddeman, W.E.; Schweitzer, G.K.; Bull, W.E., Photoelectron spectra of methane, silane, germane, methyl fluoride, difluoromethane, and trifluoromethane, J. Chem. Phys., 1970, 53, 768. [all data]

Brundle, Robin, et al., 1970
Brundle, C.R.; Robin, M.B.; Basch, H., Electronic energies and electronic structures of the fluoromethanes, J. Chem. Phys., 1970, 53, 2196. [all data]

Harshbarger, Robin, et al., 1973
Harshbarger, W.R.; Robin, M.B.; Lassettre, E.N., The electron impact spectra of the fluoromethanes, J. Electron Spectrosc. Relat. Phenom., 1973, 1, 319. [all data]

Lifshitz and Long, 1965
Lifshitz, C.; Long, F.A., Appearance potentials and mass spectra of fluorinated ethylenes. II. Heats offormation of fluorinated species and their positive ions, J. Phys. Chem., 1965, 69, 3731. [all data]

Steele, 1964
Steele, W.C., Appearance potentials of the difluoromethylene positive ion, J. Phys. Chem., 1964, 68, 2359. [all data]

Lossing, 1972
Lossing, F.P., Free radicals by mass spectrometry. XLIV. Ionization potentials bond dissociation energies for chloro-and fluoromethyl radicals, Bull. Soc. Chim. Belg., 1972, 81, 125. [all data]

Martin, Lampe, et al., 1966
Martin, R.H.; Lampe, F.W.; Taft, R.W., An electron-impact study of ionization and dissociation in methoxy- and halogen- substituted methanes, J. Am. Chem. Soc., 1966, 88, 1353. [all data]

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

Zenkevich and Rodin, 2004
Zenkevich, I.G.; Rodin, A.A., Gas chromatographic identification of some volatile toxic fluorine containing compounds by precalculated retention indices, J. Ecol. Chem. (Rus.), 2004, 13, 1, 22-28. [all data]


Notes

Go To: Top, Gas 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), Gas Chromatography, Site Links, NIST Free Links, References