Difluoromethane

• Formula: CH₂F₂
• Molecular weight: 52.0234
• IUPAC Standard InChI: InChI=1S/CH2F2/c2-1-3/h1H2 Copy

  
• IUPAC Standard InChIKey: RWRIWBAIICGTTQ-UHFFFAOYSA-N Copy
• CAS Registry Number: 75-10-5
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: Freon 32; Methane, difluoro-; Methylene fluoride; Carbon fluoride hydride; Genetron 32; Methylene difluoride; CH2F2; R 32; HFC 32; R 32 (refrigerant)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Phase change data
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • Gas Chromatography
  • Fluid Properties
• 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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Gas Phase Heat Capacity (Shomate Equation)

C_p° = 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
    C_p = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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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^- +  =

By formula: CHF₂^- + H⁺ = CH₂F₂

 +  = ( • )

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

C₅O₅W (g) +  (g) = C₆H₂F₂O₅W (g)

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

 +  =  + 

By formula: CH₂F₂ + Br₂ = HBr + CHBrF₂

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, Reaction thermochemistry data, 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.

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 ΔH°f (CHF₂Br,g), Trans. Faraday Soc., 1974, 17, 1366-1375. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  ΔcH°gas	Enthalpy of combustion of gas at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  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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