Methyl fluoride

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.


Gas phase thermochemistry data

Go To: Top, Gas phase ion energetics data, IR Spectrum, Vibrational and/or electronic energy levels, 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Δfgas-55.999kcal/molReviewChase, 1998Data last reviewed in December, 1963
Δfgas-59.0kcal/molIonLias, Karpas, et al., 1985ALS
Quantity Value Units Method Reference Comment
gas,1 bar53.260cal/mol*KReviewChase, 1998Data last reviewed in December, 1963

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.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

Temperature (K) 298. to 1200.1200. to 6000.
A -2.10387021.18760
B 37.011502.413841
C -21.78540-0.463092
D 5.1505910.030811
E 0.162692-5.145550
F -56.28989-73.38301
G 41.5175964.53979
H -56.00010-56.00010
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in December, 1963 Data last reviewed in December, 1963

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, IR Spectrum, Vibrational and/or electronic energy levels, References, Notes

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
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard

View reactions leading to CH3F+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)12.50 ± 0.04eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)143.1kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity136.6kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
12.45PEKimura, Katsumata, et al., 1981LLK
12.54PEBieri, Asbrink, et al., 1981LLK
12.54PEBrundle, Robin, et al., 1970RDSH
12.50PIKrauss, Walker, et al., 1968RDSH
13.04PEKimura, Katsumata, et al., 1981Vertical value; LLK
13.05PEUehara, Saito, et al., 1973Vertical value; LLK
13.05EIHarshbarger, Robin, et al., 1973Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH2F+13.6 ± 0.2HEIHolmes, Lossing, et al., 1983LBLHLM
CH2F+13.37HPIKrauss, Walker, et al., 1968RDSH
CH2F+13.25 ± 0.06HEIMartin, Lampe, et al., 1966RDSH
CH3+12.56F-PIKrauss, Walker, et al., 1968RDSH
CH3+16.25FPIKrauss, Walker, et al., 1968RDSH

De-protonation reactions

CH2F- + Hydrogen cation = Methyl fluoride

By formula: CH2F- + H+ = CH3F

Quantity Value Units Method Reference Comment
Δr419.7 ± 4.6kcal/molEIAERogers, Simpson, et al., 2010gas phase; B
Δr409.0 ± 4.0kcal/molCIDTGraul and Squires, 1990gas phase; B
Quantity Value Units Method Reference Comment
Δr400.6 ± 4.1kcal/molH-TSGraul and Squires, 1990gas phase; B

IR Spectrum

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Vibrational and/or electronic energy levels, 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

Gas Phase Spectrum

Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.

Additional Data

View image of digitized spectrum (can be printed in landscape orientation).

View spectrum image in SVG format.

Download spectrum in JCAMP-DX format.

Owner NIST Standard Reference Data Program
Collection (C) 2018 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin Sadtler Research Labs Under US-EPA Contract
State gas

This IR spectrum is from the NIST/EPA Gas-Phase Infrared Database .


Vibrational and/or electronic energy levels

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, 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: Takehiko Shimanouchi

Symmetry:   C     Symmetry Number σ = 3


 Sym.   No   Approximate   Selected Freq.  Infrared   Raman   Comments 
 Species   type of mode   Value   Rating   Value  Phase  Value  Phase

a1 1 CH3 s-str 2930  E 2964 VS gas FR(2ν5)
a1 1 CH3 s-str 2930  E 2863 S gas FR(2ν5)
a1 2 CH3 s-deform 1464  A 1464 S gas
a1 3 CF str 1049  A 1048.6 S gas
e 4 CH3 d-str 3006  A 3005.8 S gas
e 5 CH3 d-deform 1467  A 1466.5 M gas
e 6 CH3 rock 1182  A 1182.4 M gas

Source: Shimanouchi, 1972

Notes

VSVery strong
SStrong
MMedium
FRFermi resonance with an overtone or a combination tone indicated in the parentheses.
A0~1 cm-1 uncertainty
E15~30 cm-1 uncertainty

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, Vibrational and/or electronic energy levels, 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]

Lias, Karpas, et al., 1985
Lias, S.G.; Karpas, Z.; Liebman, J.F., Halomethylenes: effects of halogen substitution on absolute heats of formation, J. Am. Chem. Soc., 1985, 107, 6089-6096. [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]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Bieri, Asbrink, et al., 1981
Bieri, G.; Asbrink, L.; Von Niessen, W., 30.4 nm He(II) photoelectron spectra of organic molecules. Part IV. Fluoro-compounds (C,H,F), J. Electron Spectrosc. Relat. Phenom., 1981, 23, 281. [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]

Krauss, Walker, et al., 1968
Krauss, M.; Walker, J.A.; Dibeler, V.H., Mass spectrometric study of photoionization. X. Hydrogen chloride and methyl halides, J. Res. NBS, 1968, 72A, 281. [all data]

Uehara, Saito, et al., 1973
Uehara, Y.; Saito, N.; Yonezawa, T., Ionization potentials of trifluoromethyl and methyl halides by photoelectron spectroscopy and calculations by extended Hucket and CNDO/2 methods, Chem. Lett., 1973, 495. [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]

Holmes, Lossing, et al., 1983
Holmes, J.L.; Lossing, F.P.; Terlouw, J.K.; Burgers, P.C., Novel gas-phase ions. The radical cations [CH2XH]+. (X = F, Cl, Br, I, OH, NH2, SH) and [CH2CH2NH3]+., Can. J. Chem., 1983, 61, 2305. [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]

Rogers, Simpson, et al., 2010
Rogers, N.J.; Simpson, M.J.; Tuckett, R.P.; Dunn, K.F.; Latimer, C.J., Vacuum-UV negative photoion spectroscopy of CH3F, CH3Cl and CH3Br, Phys. Chem. Chem. Phys., 2010, 12, 36, 10971-10980, https://doi.org/10.1039/c0cp00234h . [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]

Shimanouchi, 1972
Shimanouchi, T., Tables of Molecular Vibrational Frequencies Consolidated Volume I, National Bureau of Standards, 1972, 1-160. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, Vibrational and/or electronic energy levels, References