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Experimental data for CH2F2 (Methane, difluoro-)

22 02 02 11 45
Other names
Carbon fluoride hydride (CF2H2); Difluoromethane; Freon 32; Genetron 32; Methane, difluoro-; Methylene difluoride; Methylene fluoride; R 32;
InChI=1S/CH2F2/c2-1-3/h1H2 RWRIWBAIICGTTQ-UHFFFAOYSA-N FCF Difluoromethane
State Conformation
1A1 C2V
Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)
Property Value Uncertainty units Reference Comment
Hfg(298.15K) enthalpy of formation -452.20 1.70 kJ mol-1 Gurvich
Hfg(0K) enthalpy of formation -444.55 1.70 kJ mol-1 Gurvich
Entropy (298.15K) entropy 246.71   J K-1 mol-1 Gurvich
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 10.69   kJ mol-1 Gurvich
Heat Capacity (298.15K) heat capacity 42.88   J K-1 mol-1 Gurvich
Information can also be found for this species in the NIST Chemistry Webbook
Vibrational levels (cm-1) vibrations
Mode Number Symmetry Frequency Intensity Comment Description
Fundamental(cm-1) Harmonic(cm-1) Reference (km mol-1) unc. Reference
1 A1 2948   1980Kon/Nak:5409 22.4   1980Kon/Nak:5409 CH2 s-stretch
2 A1 1508   1980Kon/Nak:5409 0.0   1980Kon/Nak:5409 CH2 scissors
3 A1 1111   1980Kon/Nak:5409       intensity of bands 3, 7 and 9 together 333.8 CF2 s-str
4 A1 529   1980Kon/Nak:5409 4.7   1980Kon/Nak:5409 CF2 sciss
5 A2 1262   1974sve/kov       CH2 twist
6 B1 3014   1980Kon/Nak:5409 43.3   1980Kon/Nak:5409 CH2 a-str
7 B1 1178   1980Kon/Nak:5409       intensity of bands 3, 7 and 9 together 333.8 CH2 rock
8 B2 1435   1980Kon/Nak:5409 9.9   1980Kon/Nak:5409 CH2 wag
9 B2 1090   1980Kon/Nak:5409       intensity of bands 3, 7 and 9 together 333.8 CF2 a-str

vibrational zero-point energy: 7037.5 cm-1 (from fundamental vibrations)
Calculated vibrational frequencies for CH2F2 (Methane, difluoro-).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
1.59213 0.35378 0.30854 1978Hir:409

Calculated rotational constants for CH2F2 (Methane, difluoro-).
Product of moments of inertia moments of inertia
27565.24amu3Å6   1.26220481093086E-115gm3 cm6
Geometric Data
picture of Methane, difluoro-

Point Group C2v

Internal coordinates
distances (r) in Å, angles (a) in degrees, dihedrals (d) in degrees
Description Value unc. Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rCF 1.351 0.001 1 4 1978hir:145 re
rCH 1.084 0.003 1 2 1978hir:145 re
aFCF 108.49 0.06 4 1 5 1978hir:145
aHCH 112.8 0.3 2 1 3 1978hir:145
aHCF 108.87 2 1 4 1978hir:145 by symmetry

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 0.5003
H2 -0.9029 0.0000 1.1002
H3 0.9029 0.0000 1.1002
F4 0.0000 1.0962 -0.2890
F5 0.0000 -1.0962 -0.2890

Atom - Atom Distances bond lengths
Distances in Å
  C1 H2 H3 F4 F5
C1   1.08401.08401.35081.3508
H2 1.0840   1.80581.98661.9866
H3 1.08401.8058   1.98661.9866
F4 1.35081.98661.9866   2.1924
F5 1.35081.98661.98662.1924  

Calculated geometries for CH2F2 (Methane, difluoro-).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
H2 C1 H3 112.800 H2 C1 F4 108.866
H2 C1 F5 108.866 H3 C1 F4 108.866
H3 C1 F5 108.866 F4 C1 F5 108.490

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-F 2
H-C 2

Atom 1 Atom 2
C1 H2
C1 H3
C1 F4
C1 F5
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1A1

Ionization Energies (eV)
Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
12.710   13.270   webbook
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
State Config State description Conf description Exp. min. Dipole (Debye) Reference comment Point Group Components
x y z total dipole quadrupole
1 1 1A1 C2v True       1.970 NSRDS-NBS10 MW C2v 1 2
Experimental dipole measurement abbreviations: MW microwave; DT Dielectric with Temperature variation; DR Indirect (usually an upper limit); MB Molecular beam
Calculated electric dipole moments for CH2F2 (Methane, difluoro-).
Electric quadrupole moment quadrupole
State Config State description Conf description Exp. min. Quadrupole (D Å) Reference comment Point Group Components
xx yy zz dipole quadrupole
1 1 1A1 C2v True 2.200 -4.100 1.900 1984Gra/Gub -4.1+-0.4, 2.2+-0.6, 1.9+-0.3 C2v 1 2

Calculated electric quadrupole moments for CH2F2 (Methane, difluoro-).
Electric dipole polarizability (Å3) polarizability
alpha unc. Reference
2.761   1998Gus/Rui:163

Calculated electric dipole polarizability for CH2F2 (Methane, difluoro-).

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squib reference DOI
1974sve/kov L.M. Sverdlov, M. A. Kovner, E. P. Krainov, "Vibrational Spectra of Polyatomic Molecules" Wiley, New York 1974  
1978hir:145 Hirota, H. Anharmonic Potential Function and Equilibrium Structure of Methylene Fluoride, J. Mol. Spec. 71, 145-159, 1978 10.1016/0022-2852(78)90079-6
1978Hir:409 Hirota, E. "Microwave Spectrum of Methylene Fluoride in Excited Vibrational States." Journal of Molecular Spectroscopy. 69, 409-420 (1978) 10.1016/0022-2852(78)90234-5
1980Kon/Nak:5409 S Kondo, T Nakanaga, S Saeki,"Infrared intensities and Coriolis interactions in methylene fluoride" J. Chem. Phys. 73(11), 5409, 1980 10.1063/1.440086
1984Gra/Gub CG Gray, KE Gubbins "Theory of molecular fluids. Volume 1:Fundamentals" Clarendon Press, Oxford 1984  
1998Gus/Rui:163 M Gussoni, R Rui, G Zerbi "Electronic and relaxation contribution to linear molecular polarizability. An analysis of the experimental values" J. Mol. Struct. 447 (1998) 163-215 10.1016/S0022-2860(97)00292-5
Gurvich Gurvich, L.V.; Veyts, I. V.; Alcock, C. B., Thermodynamic Properties of Individual Substances, Fouth Edition, Hemisphere Pub. Co., New York, 1989  
NSRDS-NBS10 R. D. Nelson Jr., D. R. Lide, A. A. Maryott "Selected Values of electric dipole moments for molecules in the gas phase" NSRDS-NBS10, 1967 10.6028/NBS.NSRDS.10
webbook NIST Chemistry Webbook ( 10.18434/T4D303

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