Methyl cation
- Formula: CH3+
- Molecular weight: 15.0340
- IUPAC Standard InChIKey: JUHDUIDUEUEQND-UHFFFAOYSA-N
- CAS Registry Number: 14531-53-4
- 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. - Permanent link for this species. Use this link for bookmarking this species for future reference.
- Information on this page:
- Other data available:
- Data at other public NIST sites:
- Options:
Reaction thermochemistry data
Go To: Top, Gas phase ion energetics 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 as indicated in comments:
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. 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: CH3+ + Xe = (CH3+ • Xe)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 213. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
ΔrH° | 231. ± 10. | kJ/mol | ICR | Hovey and McMahon, 1986 | gas phase; switching reaction(CH3+)CH3F, Entropy change calculated or estimated; M |
By formula: CH3+ + Kr = (CH3+ • Kr)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 184. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
ΔrH° | 200. ± 10. | kJ/mol | ICR | Hovey and McMahon, 1987 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated; M |
CH2- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1711.7 ± 1.7 | kJ/mol | D-EA | Leopold, Murray, et al., 1985 | gas phase; Singlet-triplet splitting of CH2 = 9.0 kcal; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1679.5 ± 2.0 | kJ/mol | H-TS | Leopold, Murray, et al., 1985 | gas phase; Singlet-triplet splitting of CH2 = 9.0 kcal; B |
By formula: CH3+ + N2O = (CH3+ • N2O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 221. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + HBr = (CH3+ • HBr)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 232. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + CF3I = (CH3+ • CF3I)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 251. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + F2O2S = (CH3+ • F2O2S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 231. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + O2S = (CH3+ • O2S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 254. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + HCl = (CH3+ • HCl)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 216. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + F3N = (CH3+ • F3N)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 224. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + Cl2O2S = (CH3+ • Cl2O2S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 260. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + CO2 = (CH3+ • CO2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 207. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + C2ClF3O = (CH3+ • C2ClF3O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 251. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + COS = (CH3+ • COS)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 239. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + CH3F = (CH3+ • CH3F)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 230. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + C3F6O = (CH3+ • C3F6O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 245. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + CH3Br = (CH3+ • CH3Br)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 265. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + CH3Cl = (CH3+ • CH3Cl)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 259. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + CS2 = (CH3+ • CS2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 252. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + CBrF3 = (CH3+ • CBrF3)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 224. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: CH3+ + CClF3 = (CH3+ • CClF3)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 221. | kJ/mol | PHPMS | McMahon, Heinis, et al., 1988 | gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 202. kJ/mol; Foster, Williamson, et al., 1974; M |
By formula: (CH3+ • 2Ar) + Ar = (CH3+ • 3Ar)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 8.2 ± 0.8 | kJ/mol | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 93.3 | J/mol*K | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
By formula: (CH3+ • 3Ar) + Ar = (CH3+ • 4Ar)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 8.2 ± 0.8 | kJ/mol | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 88.3 | J/mol*K | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
By formula: (CH3+ • 4Ar) + Ar = (CH3+ • 5Ar)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 8.1 ± 0.8 | kJ/mol | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 86.2 | J/mol*K | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
By formula: (CH3+ • 5Ar) + Ar = (CH3+ • 6Ar)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 8. ± 1. | kJ/mol | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 87.9 | J/mol*K | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
By formula: (CH3+ • 6Ar) + Ar = (CH3+ • 7Ar)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 8. ± 2. | kJ/mol | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 88.7 | J/mol*K | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
By formula: (CH3+ • Ar) + Ar = (CH3+ • 2Ar)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 9.5 ± 0.8 | kJ/mol | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 65.7 | J/mol*K | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
By formula: CH3+ + Ar = (CH3+ • Ar)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 47.3 ± 8.4 | kJ/mol | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 84.1 | J/mol*K | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; M |
By formula: CH3+ + C3H7Cl = (CH3+ • C3H7Cl)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 320. | kJ/mol | PHPMS | Sharma, Meza de Hojer, et al., 1985 | gas phase; from i-C3H7+ + CH3Cl; Cox and Pilcher, 1970, Rosenstock, Buff, et al., 1982, Sen Sharma and Kebarle, 1978; M |
By formula: CH3+ + C2H5Cl = (CH3+ • C2H5Cl)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 300. | kJ/mol | PHPMS | Sharma, Meza de Hojer, et al., 1985 | gas phase; from Et+ + CH3Cl; Cox and Pilcher, 1970, Rosenstock, Buff, et al., 1982; Sen Sharma and Kebarle, 1978; M |
By formula: CH3+ + C4H9Cl = (CH3+ • C4H9Cl)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 340. | kJ/mol | PHPMS | Sharma, Meza de Hojer, et al., 1985 | gas phase; from t-C4H9+ + CH3Cl; Cox and Pilcher, 1970, Rosenstock, Buff, et al., 1982; M |
By formula: (CH3+ • 7Ar) + Ar = (CH3+ • 8Ar)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 8.08 | kJ/mol | PHPMS | Hiraoka, Kudaka, et al., 1991 | gas phase; Entropy change calculated or estimated; M |
By formula: CH3+ + N2 = (CH3+ • N2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 203. | kJ/mol | PDiss | Foster, Williamson, et al., 1974 | gas phase; M |
Gas phase ion energetics data
Go To: Top, Reaction thermochemistry 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: John E. Bartmess
De-protonation reactions
CH2- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1711.7 ± 1.7 | kJ/mol | D-EA | Leopold, Murray, et al., 1985 | gas phase; Singlet-triplet splitting of CH2 = 9.0 kcal |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1679.5 ± 2.0 | kJ/mol | H-TS | Leopold, Murray, et al., 1985 | gas phase; Singlet-triplet splitting of CH2 = 9.0 kcal |
References
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
Hovey and McMahon, 1986
Hovey, J.K.; McMahon, T.B.,
C-Xe Bond strength in the methylxenonium cation determined from ion cyclotron resonance methyl cation exchange equilibria,
J. Am. Chem. Soc., 1986, 108, 528. [all data]
Hovey and McMahon, 1987
Hovey, J.K.; McMahon, T.B.,
Bond Strength in the Methylkryptonium Ion Determined from Ion Cyclotron Resonance Methyl Cation Exchange Equilibria,
J. Phys. Chem., 1987, 91, 17, 4560, https://doi.org/10.1021/j100301a028
. [all data]
Leopold, Murray, et al., 1985
Leopold, D.G.; Murray, K.K.; Miller, A.E.S.; Lineberger, W.C.,
Methylene: A study of the X3B1 and the 1A1 states by photoelectron spectroscopy of CH2- and CD2-,
J. Chem. Phys., 1985, 83, 4849. [all data]
Hiraoka, Kudaka, et al., 1991
Hiraoka, K.; Kudaka, I.; Yamabe, S.,
A Charge-Transfer Complex CH3+ Ar in the Gas Phase,
Chem. Phys. Lett., 1991, 178, 1, 103, https://doi.org/10.1016/0009-2614(91)85060-A
. [all data]
Sharma, Meza de Hojer, et al., 1985
Sharma, D.M.S.; Meza de Hojer, S.; Kebarle, P.,
Stabilities of halonium ions from a study of gas-phase equilibria R+ + XR' = (RXR')+,
J. Am. Chem. Soc., 1985, 107, 13, 3757, https://doi.org/10.1021/ja00299a002
. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds
in Academic Press, New York, 1970. [all data]
Rosenstock, Buff, et al., 1982
Rosenstock, H.M.; Buff, R.; Ferreira, M.A.A.; Lias, S.G.; Parr, A.C.; Stockbauer, R.L.; Holmes, J.L.,
Fragmentation mechanism and energetics of some alkyl halide ions,
J. Am. Chem. Soc., 1982, 104, 2337. [all data]
Sen Sharma and Kebarle, 1978
Sen Sharma, D.K.; Kebarle, P.,
Binding Energies and Stabilities of Chloronium Ions from Study of the Gas - Phase Equilibria: R1+ + ClR2 = R1ClR2+,
J. Am. Chem. Soc., 1978, 100, 18, 5826, https://doi.org/10.1021/ja00486a039
. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
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.
- Customer support for NIST Standard Reference Data products.