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II.A.1. (XV.A.)

Listing of experimental data for CH3F (Methyl fluoride)

Other names
Fluoromethane; Freon 41; Methane, fluoro-; Methyl fluoride; UN 2454;
InChI=1/CH3F/c1-2/h1H3 CF Fluoromethane
State Conformation
1A1 C3V
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 -255.00 15.00 kJ mol-1 Gurvich
Hfg(0K) enthalpy of formation -246.97 15.00 kJ mol-1 Gurvich
Entropy (298.15K) entropy 222.82   J K-1 mol-1 Gurvich
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity 10.14   kJ mol-1 Gurvich
Heat Capacity (298.15K) heat capacity 37.50   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 (cm-1) Frequency Reference Intensity (km mol-1) Int. unc. Intensity Reference Comment
1 A1 2930 Shim 37.4   1952Bar/McK:1494 Intensity from 1952Bar/McK:1494
2 A1 1464 Shim 3.4   1952Bar/McK:1494
3 A1 1049 Shim 108.4   1952Bar/McK:1494
4 E 3006 Shim 37.4   1952Bar/McK:1494
5 E 1467 Shim 6.0   1952Bar/McK:1494
6 E 1182 Shim 1.7   1952Bar/McK:1494

vibrational zero-point energy: 8376.5 cm-1
Calculated vibrational frequencies for CH3F (Methyl fluoride).
Gas-phase IR spectra can be found in the NIST Chemistry Webbook here.
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
5.18200 0.85179 0.85179 1993Pap/Hsu:33

Calculated rotational constants for CH3F (Methyl fluoride).

Product of moments of inertia moments of inertia
1274.156amu3Å6   5.83432299759228E-117gm3 cm6

Geometric Data
picture of Methyl fluoride

Point Group C3v

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
rCH 1.087   1 3 1999Dem/Bre:129
rCF 1.383   1 2 1999Dem/Bre:129
aHCH 110.2 3 1 4 1999Dem/Bre:129
aHCF 108.73 2 1 3 1999Dem/Bre:129 From symmetry

Atom x (Å) y (Å) z (Å)
C1 0.0000 0.0000 -0.6289
F2 0.0000 0.0000 0.7541
H3 0.0000 1.0201 -1.0043
H4 0.8835 -0.5101 -1.0043
H5 -0.8835 -0.5101 -1.0043

Atom - Atom Distances bond lengths
Distances in Å
  C1 F2 H3 H4 H5
C1   1.38301.08701.08701.0870
F2 1.3830   2.03282.03282.0328
H3 1.08702.0328   1.76691.7669
H4 1.08702.03281.7669   1.7669
H5 1.08702.03281.76691.7669  

Calculated geometries for CH3F (Methyl fluoride).

Experimental Bond Angles (degrees) from cartesians bond angles
atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
F2 C1 H3 110.200 F2 C1 H4 110.200
F2 C1 H5 110.200 H3 C1 H4 108.733
H3 C1 H5 108.733 H4 C1 H5 108.733

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 3
C-F 1

Atom 1 Atom 2
C1 F2
C1 H3
C1 H4
C1 H5

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
12.500 0.040 13.040   webbook

Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Dipole (Debye) Reference comment
1.850 NSRDS-NBS10  

Calculated electric dipole moments for CH3F (Methyl fluoride).
Electric quadrupole moment quadrupole
Quadrupole (D Å) Reference comment
xx yy zz
0.700 0.700 -1.400 1971Fly/Ben:225 +-1.1

Calculated electric quadrupole moments for CH3F (Methyl fluoride).
Electric dipole polarizability (Å3) polarizability
alpha unc. Reference
2.540   1997Oln/Can:59

Calculated electric dipole polarizability for CH3F (Methyl fluoride).

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squib reference DOI
1971Fly/Ben:225 WH Flygare, RC Benson "The molecular Zeeman effect in diamagnetic molecules and the determination of molecular magnetic moments (g values), magnetic susceptibilities, and molecular quadrupole moments" Mol. Phys. 1971, 20 (2), 225-250 10.1080/00268977100100221
1993Pap/Hsu:33 Papousek, D.; Hsu, Y.C.; Chen, H.S.; Pracna, P.; Klee, S.; Winnewisser, M. "Far Infrared Specturm and Ground State Parameters of 12CH3F." Journal of Molecular Spectroscopy. 159, 33-41 (1993) 10.1006/jmsp.1993.1102
1997Oln/Can:59 TN Olney, NM Cann, G Cooper, CE Brion, Absolute scale determination for photoabsorption spectra and the calculation of molecular properties using dipole sum-rules, Chem. Phys. 223 (1997) 59-98 10.1016/S0301-0104(97)00145-6
1999Dem/Bre:129 Demaison, Breidung, Thiel, Papousek, The Equilibrium Structure of Methyl Fluoride, Structural Chemistry, Vol. 10, #2, pgs. 129-133 10.1023/A:1022085314343
Gurvich Gurvich, L.V.; Veyts, I. V.; Alcock, C. B., Thermodynamic Properties of Individual Substances, Fouth Edition, Hemisphere Pub. Co., New York, 1989 10.1351/pac198961061027
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  
Shim Shimanouchi, T. , Tables of Molecular Vibrational Frequencies, Consolidated Volume 1, NSRDS NBS-39  
webbook NIST Chemistry Webbook (  

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