Methyl fluoride
- Formula: CH3F
- Molecular weight: 34.0329
- IUPAC Standard InChIKey: NBVXSUQYWXRMNV-UHFFFAOYSA-N
- CAS Registry Number: 593-53-3
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: Fluoromethane; Methane, fluoro-; Freon 41; CH3F; UN 2454; R 41; HFC-41; Refrigerant gas R 41
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Gas phase thermochemistry data
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Gas Chromatography, 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 |
---|---|---|---|---|---|
ΔfH°gas | -55.999 | kcal/mol | Review | Chase, 1998 | Data last reviewed in December, 1963 |
ΔfH°gas | -59.0 | kcal/mol | Ion | Lias, Karpas, et al., 1985 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 53.260 | cal/mol*K | Review | Chase, 1998 | Data 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.
Temperature (K) | 298. to 1200. | 1200. to 6000. |
---|---|---|
A | -2.103870 | 21.18760 |
B | 37.01150 | 2.413841 |
C | -21.78540 | -0.463092 |
D | 5.150591 | 0.030811 |
E | 0.162692 | -5.145550 |
F | -56.28989 | -73.38301 |
G | 41.51759 | 64.53979 |
H | -56.00010 | -56.00010 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in December, 1963 | Data last reviewed in December, 1963 |
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
RCD - Robert C. Dunbar
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
By formula: Cl- + CH3F = (Cl- • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 11.5 ± 2.0 | kcal/mol | IMRE | Larson and McMahon, 1984 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 20.3 | cal/mol*K | N/A | Larson and McMahon, 1984 | gas phase; switching reaction(Cl-)CH3Cl, Entropy change calculated or estimated; Larson and McMahon, 1984, 2; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 5.4 | kcal/mol | ICR | Larson and McMahon, 1984 | gas phase; switching reaction(Cl-)CH3Cl, Entropy change calculated or estimated; Larson and McMahon, 1984, 2; M |
CH2F- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 419.7 ± 4.6 | kcal/mol | EIAE | Rogers, Simpson, et al., 2010 | gas phase; B |
ΔrH° | 409.0 ± 4.0 | kcal/mol | CIDT | Graul and Squires, 1990 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 400.6 ± 4.1 | kcal/mol | H-TS | Graul and Squires, 1990 | gas phase; B |
By formula: HO2S+ + CH3F = (HO2S+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 25.3 | kcal/mol | PHPMS | McMahon and Kebarle, 1986 | gas phase; switching reaction(SO2H+)SO2; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 28.4 | cal/mol*K | PHPMS | McMahon and Kebarle, 1986 | gas phase; switching reaction(SO2H+)SO2; M |
By formula: CH3+ + CH3F = (CH3+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 54.9 | kcal/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 48.3 kcal/mol; Foster, Williamson, et al., 1974; M |
By formula: Li+ + CH3F = (Li+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 31. | kcal/mol | ICR | Staley and Beauchamp, 1975 | gas phase; switching reaction(Li+)H2O, from graph; Dzidic and Kebarle, 1970 interpolated; M |
By formula: CH6N+ + CH3F = (CH6N+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 11.8 | kcal/mol | PHPMS | Meot-Ner, 1984 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 23.3 | cal/mol*K | PHPMS | Meot-Ner, 1984 | gas phase; M |
By formula: CH4F+ + CH3F = (CH4F+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 32. ± 2. | kcal/mol | PHPMS | McMahon and Kebarle, 1986 | gas phase; switching reaction(SO2H+)SO2; Lias, Liebman, et al., 1984; M |
C5O5W (g) + (g) = C6H3FO5W (g)
By formula: C5O5W (g) + CH3F (g) = C6H3FO5W (g)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -11.2 ± 3.0 | kcal/mol | EqG | Brown, Ishikawa, et al., 1990 | Temperature range: ca. 300-350 K; MS |
By formula: Al+ + CH3F = (Al+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 21.5 ± 2.0 | kcal/mol | EqG | Bouchard, Brenner, et al., 1997 | RCD |
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
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 ± 0.04 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 143.1 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 136.6 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
12.45 | PE | Kimura, Katsumata, et al., 1981 | LLK |
12.54 | PE | Bieri, Asbrink, et al., 1981 | LLK |
12.54 | PE | Brundle, Robin, et al., 1970 | RDSH |
12.50 | PI | Krauss, Walker, et al., 1968 | RDSH |
13.04 | PE | Kimura, Katsumata, et al., 1981 | Vertical value; LLK |
13.05 | PE | Uehara, Saito, et al., 1973 | Vertical value; LLK |
13.05 | EI | Harshbarger, Robin, et al., 1973 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
CH2F+ | 13.6 ± 0.2 | H | EI | Holmes, Lossing, et al., 1983 | LBLHLM |
CH2F+ | 13.37 | H | PI | Krauss, Walker, et al., 1968 | RDSH |
CH2F+ | 13.25 ± 0.06 | H | EI | Martin, Lampe, et al., 1966 | RDSH |
CH3+ | 12.56 | F- | PI | Krauss, Walker, et al., 1968 | RDSH |
CH3+ | 16.25 | F | PI | Krauss, Walker, et al., 1968 | RDSH |
De-protonation reactions
CH2F- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 419.7 ± 4.6 | kcal/mol | EIAE | Rogers, Simpson, et al., 2010 | gas phase; B |
ΔrH° | 409.0 ± 4.0 | kcal/mol | CIDT | Graul and Squires, 1990 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 400.6 ± 4.1 | kcal/mol | H-TS | Graul and Squires, 1990 | gas phase; B |
Ion clustering data
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Gas Chromatography, 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:
RCD - Robert C. Dunbar
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
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
By formula: Al+ + CH3F = (Al+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 21.5 ± 2.0 | kcal/mol | EqG | Bouchard, Brenner, et al., 1997 | RCD |
By formula: CH3+ + CH3F = (CH3+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 54.9 | kcal/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 48.3 kcal/mol; Foster, Williamson, et al., 1974; M |
By formula: CH4F+ + CH3F = (CH4F+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 32. ± 2. | kcal/mol | PHPMS | McMahon and Kebarle, 1986 | gas phase; switching reaction(SO2H+)SO2; Lias, Liebman, et al., 1984; M |
By formula: CH6N+ + CH3F = (CH6N+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 11.8 | kcal/mol | PHPMS | Meot-Ner, 1984 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 23.3 | cal/mol*K | PHPMS | Meot-Ner, 1984 | gas phase; M |
By formula: Cl- + CH3F = (Cl- • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 11.5 ± 2.0 | kcal/mol | IMRE | Larson and McMahon, 1984 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 20.3 | cal/mol*K | N/A | Larson and McMahon, 1984 | gas phase; switching reaction(Cl-)CH3Cl, Entropy change calculated or estimated; Larson and McMahon, 1984, 2; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 5.4 | kcal/mol | ICR | Larson and McMahon, 1984 | gas phase; switching reaction(Cl-)CH3Cl, Entropy change calculated or estimated; Larson and McMahon, 1984, 2; M |
By formula: HO2S+ + CH3F = (HO2S+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 25.3 | kcal/mol | PHPMS | McMahon and Kebarle, 1986 | gas phase; switching reaction(SO2H+)SO2; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 28.4 | cal/mol*K | PHPMS | McMahon and Kebarle, 1986 | gas phase; switching reaction(SO2H+)SO2; M |
By formula: Li+ + CH3F = (Li+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 31. | kcal/mol | ICR | Staley and Beauchamp, 1975 | gas phase; switching reaction(Li+)H2O, from graph; Dzidic and Kebarle, 1970 interpolated; M |
Gas Chromatography
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, 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
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | OV-101 | 217. | Zenkevich, 2005 | 25. m/0.20 mm/0.10 μm, N2/He, 6. K/min; Tstart: 50. C; Tend: 250. C |
Normal alkane RI, non-polar column, custom temperature program
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | Porapack Q | 173. | Zenkevich and Rodin, 2004 | Program: not specified |
References
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Gas Chromatography, 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]
Larson and McMahon, 1984
Larson, J.W.; McMahon, T.B.,
Hydrogen bonding in gas phase anions. An experimental investigation of the interaction between chloride ion and bronsted acids from ICR chloride exchange equilibria,
J. Am. Chem. Soc., 1984, 106, 517. [all data]
Larson and McMahon, 1984, 2
Larson, J.W.; McMahon, T.B.,
Gas phase negative ion chemistry of alkylchloroformates,
Can. J. Chem., 1984, 62, 675. [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]
McMahon and Kebarle, 1986
McMahon, T.B.; Kebarle, P.,
Strong hydrogen bonding in gas-phase ions: A high pressure mass spectrometric study of formation and energetics of methyl fluoride proton bound dimer,
J. Am. Chem. Soc., 1986, 108, 6502. [all data]
McMahon, Heinis, et al., 1988
McMahon, T.; Heinis, T.; Nicol, G.; Hovey, J.K.; Kebarle, P.,
Methyl Cation Affinities,
J. Am. Chem. Soc., 1988, 110, 23, 7591, https://doi.org/10.1021/ja00231a002
. [all data]
Foster, Williamson, et al., 1974
Foster, M.S.; Williamson, A.D.; Beauchamp, J.L.,
Photoionization mass spectrometry of trans-azomethane,
Int. J. Mass Spectrom. Ion Phys., 1974, 15, 429. [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]
Meot-Ner, 1984
Meot-Ner, (Mautner)M.,
The Ionic Hydrogen Bond and Ion Solvation. 1. -NH+ O-, -NH+ N- and -OH+ O- Bonds. Correlations with Proton Affinity. Deviations Due to Structural Effects,
J. Am. Chem. Soc., 1984, 106, 5, 1257, https://doi.org/10.1021/ja00317a015
. [all data]
Lias, Liebman, et al., 1984
Lias, S.G.; Liebman, J.F.; Levin, R.D.,
Evaluated gas phase basicities and proton affinities of molecules heats of formation of protonated molecules,
J. Phys. Chem. Ref. Data, 1984, 13, 695. [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]
Bouchard, Brenner, et al., 1997
Bouchard, F.; Brenner, V.; Carra, C.; Hepburn, J.W.; Koyanagi, G.K.; McMahon, T.B.; Ohanessian, G.; Peschke, M.,
Energetics and Structure of Complexes of Al+ with Small Organic Molecules in the Gas Phase,
J. Phys. Chem. A, 1997, 101, 33, 5885, https://doi.org/10.1021/jp9703465
. [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]
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, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Gas Chromatography, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy S°gas,1 bar Entropy of gas at standard conditions (1 bar) 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 ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
- The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
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