Methylamine
- Formula: CH5N
- Molecular weight: 31.0571
- IUPAC Standard InChIKey: BAVYZALUXZFZLV-UHFFFAOYSA-N
- CAS Registry Number: 74-89-5
- 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. - Isotopologues:
- Other names: Methanamine; Aminomethane; Carbinamine; Monomethylamine; CH3NH2; Mercurialin; Methylaminen; Metilamine; Metyloamina; UN 1061; MMA
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Gas phase thermochemistry data
Go To: Top, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), 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: Donald R. Burgess, Jr.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -23.5 | kJ/mol | N/A | Aston, Siller, et al., 1937 | Value computed using ΔfHliquid° value of -47.3±0.46 kj/mol from Aston, Siller, et al., 1937 and ΔvapH° value of 23.85 kj/mol from missing citation. |
ΔfH°gas | -12.2 | kJ/mol | N/A | Lemoult, 1907 | Value computed using ΔfHliquid° value of -36 kj/mol from Lemoult, 1907 and ΔvapH° value of 23.85 kj/mol from missing citation. |
Phase change data
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
DH - Eugene S. Domalski and Elizabeth D. Hearing
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 266.8 ± 0.3 | K | AVG | N/A | Average of 8 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 180.05 | K | N/A | Roberts, Emeleus, et al., 1939 | Uncertainty assigned by TRC = 0.4 K; TRC |
Tfus | 180.05 | K | N/A | Emeleus and Briscoe, 1937 | Uncertainty assigned by TRC = 0.3 K; TRC |
Tfus | 179.7 | K | N/A | McNeight and Smyth, 1936 | Uncertainty assigned by TRC = 0.07 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 179.7 | K | N/A | Aston, Siller, et al., 1937, 2 | Uncertainty assigned by TRC = 0.07 K; T0/K=273.16; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 430.85 | K | N/A | Li and Kiran, 1988 | Uncertainty assigned by TRC = 0.5 K; TRC |
Tc | 430.7 | K | N/A | Kay and Young, 1974 | Uncertainty assigned by TRC = 0.2 K; TRC |
Tc | 430.05 | K | N/A | Berthoud, 1917 | Uncertainty assigned by TRC = 0.7 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 76.50 | bar | N/A | Li and Kiran, 1988 | Uncertainty assigned by TRC = 1.00 bar; TRC |
Pc | 76.14 | bar | N/A | Kay and Young, 1974 | Uncertainty assigned by TRC = 0.04 bar; TRC |
Pc | 74.5752 | bar | N/A | Berthoud, 1917 | Uncertainty assigned by TRC = 0.6079 bar; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.1385 | l/mol | N/A | Li and Kiran, 1988 | Uncertainty assigned by TRC = 0.001 l/mol; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 23.85 | kJ/mol | N/A | Majer and Svoboda, 1985 |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
25.811 | 266.84 | N/A | Aston, Siller, et al., 1937, 3 | DH |
25.6 | 266.8 | N/A | Majer and Svoboda, 1985 | |
24.8 | 334. | A | Stephenson and Malanowski, 1987 | Based on data from 319. to 381. K.; AC |
23.5 | 388. | A | Stephenson and Malanowski, 1987 | Based on data from 373. to 430. K.; AC |
26.1 | 278. | A | Stephenson and Malanowski, 1987 | Based on data from 263. to 329. K.; AC |
27.2 | 258. | A | Stephenson and Malanowski, 1987 | Based on data from 223. to 273. K. See also Dykyj, 1970.; AC |
25.81 ± 0.13 | 266.84 | V | Aston, Siller, et al., 1937 | ALS |
27.4 | 252. | N/A | Aston, Siller, et al., 1937, 3 | Based on data from 190. to 267. K. See also Boublik, Fried, et al., 1984.; AC |
Entropy of vaporization
ΔvapS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
96.73 | 266.84 | Aston, Siller, et al., 1937, 3 | DH |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (bar)
T = temperature (K)
View plot Requires a JavaScript / HTML 5 canvas capable browser.
Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
190.06 to 266.92 | 4.520 | 1034.977 | -37.574 | Aston, Siller, et al., 1937, 3 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
6.134 | 179.70 | Aston, Siller, et al., 1937, 3 | DH |
6.13 | 179.7 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
34.13 | 179.70 | Aston, Siller, et al., 1937, 3 | DH |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), 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
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to CH5N+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 8.9 ± 0.1 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 899.0 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 864.5 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.9 | PE | Aue and Bowers, 1979 | LLK |
9.45 | EI | Baldwin, Loudon, et al., 1977 | LLK |
8.9 ± 0.1 | PE | Aue, Webb, et al., 1976 | LLK |
9.08 | PE | Vovna and Vilesov, 1974 | LLK |
8.80 ± 0.02 | PE | Maier and Turner, 1973 | LLK |
9.65 | PE | Elbel, Dieck, et al., 1982 | Vertical value; LBLHLM |
9.0 | PE | Bieri, Asbrink, et al., 1982 | Vertical value; LBLHLM |
9.58 | PE | Utsunomiya, Kobayashi, et al., 1980 | Vertical value; LLK |
9.58 | PE | Kobayashi, 1978 | Vertical value; LLK |
9.64 | PE | Kimura and Osafune, 1975 | Vertical value; LLK |
9.64 | PE | Katsumata, Iwai, et al., 1973 | Vertical value; LLK |
9.65 | PE | Ogata, Onizuka, et al., 1972 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
CH2N+ | 15.2 ± 0.3 | H2+H | EI | Collin and Franskin, 1966 | RDSH |
CH2N+[CNH2+] | 14.0 ± 0.4 | ? | EI | Burgers, Holmes, et al., 1984 | LBLHLM |
CH3+ | 14.5 | NH2 | EI | SenSharma and Franklin, 1973 | LLK |
CH3+ | 14.7 | NH2 | EI | Haney and Franklin, 1968 | RDSH |
CH3N+ | 13.3 ± 0.2 | H2 | EI | Collin and Franskin, 1966 | RDSH |
CH4N+ | 10.18 | H | EI | Lossing, Lam, et al., 1981 | LLK |
CH4N+ | 10.70 | H | EI | Loudon and Webb, 1977 | LLK |
CH4N+ | 10.55 | H | EI | Loudon and Webb, 1977 | LLK |
CH4N+ | 10.82 ± 0.15 | H | EI | Collin and Franskin, 1966 | RDSH |
CH4N+ | 10.3 ± 0.1 | H | EI | Taft, Martin, et al., 1965 | RDSH |
CH5N+ | 8.99 | ? | PI | Cornford, Frost, et al., 1971 | LLK |
CH5N+ | 9.29 | ? | CTS | Slifkin and Allison, 1967 | RDSH |
CH5N+ | 9.36 ± 0.02 | ? | EI | Collin and Franskin, 1966 | RDSH |
CH5N+ | 8.97 ± 0.02 | ? | PI | Watanabe and Mottl, 1957 | RDSH |
H2N+ | 15.9 | CH3 | EI | SenSharma and Franklin, 1973 | LLK |
NH2+ | 15.7 | CH3 | EI | Haney and Franklin, 1968 | RDSH |
De-protonation reactions
CH4N- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1682. ± 11. | kJ/mol | D-EA | Radisic, Xu, et al., 2002 | gas phase; B |
ΔrH° | 1687.0 ± 3.4 | kJ/mol | G+TS | MacKay, Hemsworth, et al., 1976 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1651. ± 11. | kJ/mol | H-TS | Radisic, Xu, et al., 2002 | gas phase; B |
ΔrG° | 1655.6 ± 2.9 | kJ/mol | IMRE | MacKay, Hemsworth, et al., 1976 | gas phase; B |
Mass spectrum (electron ionization)
Go To: Top, Gas phase thermochemistry data, Phase change data, 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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
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Additional Data
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Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | Japan AIST/NIMC Database- Spectrum MS-NW- 377 |
NIST MS number | 228024 |
References
Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Aston, Siller, et al., 1937
Aston, J.G.; Siller, C.W.; Messerly, G.H.,
Heat capacities and entropies of organic compounds. III. Methylamine from 11.5°K. to the boiling point. Heat of vaporization and vapor pressure. The entropy from molecular data,
J. Am. Chem. Soc., 1937, 59, 1743-17. [all data]
Lemoult, 1907
Lemoult, M.P.,
Recherches theoriques et experimentales sur les chaleurs de combustion et de formation des composes organiques,
Ann. Chim. Phys., 1907, 12, 395-432. [all data]
Roberts, Emeleus, et al., 1939
Roberts, E.R.; Emeleus, H.J.; Briscoe, H.V.A.,
Preparation and Prop. of Ethyldideuteramine and Dimethyldeuteramine,
J. Chem. Soc., 1939, 1939, 41. [all data]
Emeleus and Briscoe, 1937
Emeleus, H.J.; Briscoe, H.V.A.,
Preparation and Properties of Methyldideuteramine,
J. Chem. Soc., 1937, 1937, 127. [all data]
McNeight and Smyth, 1936
McNeight, S.A.; Smyth, C.P.,
Non-Rotation of Molecules in a Number of Solids,
J. Am. Chem. Soc., 1936, 58, 1718. [all data]
Aston, Siller, et al., 1937, 2
Aston, J.G.; Siller, C.W.; Messerly, G.H.,
Heat Capacities and Entropies of Organic Compounds III. Methylamine from 11.5 K to the Boiling Point. Heat of Vaporization and Vapor Pressure. The Entropy from Molecular Data,
J. Am. Chem. Soc., 1937, 59, 1743. [all data]
Li and Kiran, 1988
Li, L.; Kiran, E.,
Gas-Liquid Critical Properties of Methylamine + Nitrous Oxide and Methylamine + Ethylene Binary Mixtures,
J. Chem. Eng. Data, 1988, 33, 342. [all data]
Kay and Young, 1974
Kay, W.B.; Young, C.L.,
Int. DATA Ser., Sel. Data Mixtures, Ser. A, 1974, No. 2, 158. [all data]
Berthoud, 1917
Berthoud, A.,
Determination of Critical Temperatures and Pressures of Amines and Alkyl Chlorides,
J. Chim. Phys. Phys.-Chim. Biol., 1917, 15, 3. [all data]
Majer and Svoboda, 1985
Majer, V.; Svoboda, V.,
Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]
Aston, Siller, et al., 1937, 3
Aston, J.G.; Siller, C.W.; Messerly, G.H.,
Heat capacities and entropies of organic compounds. III. Methylamine from 12K to the boiling point. Heat of vaporization and vapor pressure. The entropy from molecular data,
J. Am. Chem. Soc., 1937, 59, 1743-1751. [all data]
Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw,
Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2
. [all data]
Dykyj, 1970
Dykyj, J.,
Petrochemica, 1970, 10, 2, 51. [all data]
Boublik, Fried, et al., 1984
Boublik, T.; Fried, V.; Hala, E.,
The Vapour Pressures of Pure Substances: Selected Values of the Temperature Dependence of the Vapour Pressures of Some Pure Substances in the Normal and Low Pressure Region, 2nd ed., Elsevier, New York, 1984, 972. [all data]
Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D.,
Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III,
J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985
. [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]
Aue and Bowers, 1979
Aue, D.H.; Bowers, M.T.,
Chapter 9. Stabilities of positive ions from equilibrium gas phase basicity measurements
in Ions Chemistry,, ed. M.T. Bowers, 1979. [all data]
Baldwin, Loudon, et al., 1977
Baldwin, M.A.; Loudon, A.G.; Webb, K.S.; Cardnell, P.C.,
Charge location and fragmentation under electron impact. V-The ionization potentials of (methylated) phosphoramides, guanidines, formamides, acetamides, ureas and thioureas,
Org. Mass Spectrom., 1977, 12, 279. [all data]
Aue, Webb, et al., 1976
Aue, D.H.; Webb, H.M.; Bowers, M.T.,
Quantitative proton affinities, ionization potentials, and hydrogen affinities of alkylamines,
J. Am. Chem. Soc., 1976, 98, 311. [all data]
Vovna and Vilesov, 1974
Vovna, V.I.; Vilesov, F.I.,
Photoelectron spectra the structure of molecular orbitals of methyl amines,
Opt. Spectrosc., 1974, 36, 251. [all data]
Maier and Turner, 1973
Maier, J.P.; Turner, D.W.,
Steric inhibition of resonance studied by molecular photoelectron spectroscopy Part 3. Anilines, Phenols and Related Compounds,
J. Chem. Soc. Faraday Trans. 2, 1973, 69, 521. [all data]
Elbel, Dieck, et al., 1982
Elbel, S.; Dieck, H.T.; Demuth, R.,
Photoelectron sSpectra of group V compounds. IX. The relative perfluoroalkyl substituent effect,
J. Fluorine Chem., 1982, 19, 349. [all data]
Bieri, Asbrink, et al., 1982
Bieri, G.; Asbrink, L.; Von Niessen, W.,
30.4-nm He(II) photoelectron spectra of organic molecules,
J. Electron Spectrosc. Relat. Phenom., 1982, 27, 129. [all data]
Utsunomiya, Kobayashi, et al., 1980
Utsunomiya, C.; Kobayashi, T.; Nagakura, S.,
Photoelectron angular distribution measurements for some aliphatic alcohols, amines, halides,
Bull. Chem. Soc. Jpn., 1980, 53, 1216. [all data]
Kobayashi, 1978
Kobayashi, T.,
A simple general tendency in photoelectron angular distributions of some monosubstituted benzenes,
Phys. Lett., 1978, 69, 105. [all data]
Kimura and Osafune, 1975
Kimura, K.; Osafune, K.,
Sum rule consideration on valence orbital ionization energies in methyl amines,
Mol. Phys., 1975, 29, 1073. [all data]
Katsumata, Iwai, et al., 1973
Katsumata, S.; Iwai, T.; Kimura, K.,
Photoelectron spectra and sum rule consideration. Higher alkyl amines and alcohols,
Bull. Chem. Soc. Jpn., 1973, 46, 3391. [all data]
Ogata, Onizuka, et al., 1972
Ogata, H.; Onizuka, H.; Nihei, Y.; Kamada, H.,
On the first bands of the photoelectron spectra of amines, alcohols, and mercaptans,
Chem. Lett., 1972, 895. [all data]
Collin and Franskin, 1966
Collin, J.E.; Franskin, M.J.,
Ionisation, dissociation et rearrangements intramoleculaires dans les amines aliphatiques par impact electronique. Cas de la methylamine et de la methylamine-Nd2,
Bull. Soc. Roy. Sci. Liege, 1966, 35, 267. [all data]
Burgers, Holmes, et al., 1984
Burgers, P.C.; Holmes, J.L.; Terlouw, J.K.,
Gaseous [H2,C,N]+ and [H3,C,N]+ ions. Generation of formation, and dissociation characteristics of [H2CN]+, [HCNH]+, [CNH2]+, [H2CNH]+, and [HCN]+,
J. Am. Chem. Soc., 1984, 106, 2762. [all data]
SenSharma and Franklin, 1973
SenSharma, D.K.; Franklin, J.L.,
Heat of formation of free radicals by mass spectrometry,
J. Am. Chem. Soc., 1973, 95, 6562. [all data]
Haney and Franklin, 1968
Haney, M.A.; Franklin, J.L.,
Correlation of excess energies of electron-impact dissociations with the translational energies of the products,
J.Chem. Phys., 1968, 48, 4093. [all data]
Lossing, Lam, et al., 1981
Lossing, F.P.; Lam, Y.-T.; Maccoll, A.,
Gas phase heats of formation of alkyl immonium ions,
Can. J. Chem., 1981, 59, 2228. [all data]
Loudon and Webb, 1977
Loudon, A.G.; Webb, K.S.,
The nature of the [C2H6N]+ and [CH4N]+ ions formed by electron impact on methylated formamides, acetamides, ureas, thioureas and hexamethylphosphoramide,
Org. Mass Spectrom., 1977, 12, 283. [all data]
Taft, Martin, et al., 1965
Taft, R.W.; Martin, R.H.; Lampe, F.W.,
Stabilization energies of substituted methyl cations. The effect of strong demand on the resonance order,
J. Am. Chem. Soc., 1965, 87, 2490. [all data]
Cornford, Frost, et al., 1971
Cornford, A.B.; Frost, D.C.; Herring, F.G.; McDowell, C.A.,
Electronic levels of methyl amines by photoelectron spectroscopy and an i.n.d.o. calculation,
Can. J. Chem., 1971, 49, 1135. [all data]
Slifkin and Allison, 1967
Slifkin, M.A.; Allison, A.C.,
Measurement of ionization potentials from contact charge transfer spectra,
Nature, 1967, 215, 949. [all data]
Watanabe and Mottl, 1957
Watanabe, K.; Mottl, J.R.,
Ionization potentials of ammonia and some amines,
J. Chem. Phys., 1957, 26, 1773. [all data]
Radisic, Xu, et al., 2002
Radisic, D.; Xu, S.J.; Bowen, K.H.,
Photoelectron spectroscopy of the anions, CH3NH- and (CH3)(2)N- and the anion complexes, H-(CH3NH2) and (CH3)(2)N-[(CH3)(2)NH),
Chem. Phys. Lett., 2002, 354, 1-2, 9-13, https://doi.org/10.1016/S0009-2614(01)01470-1
. [all data]
MacKay, Hemsworth, et al., 1976
MacKay, G.J.; Hemsworth, R.S.; Bohme, D.K.,
Absolute gas-phase acidities of CH3NH2, C2H5NH2, (CH3)2NH, and (CH3)3N,
Can. J. Chem., 1976, 54, 1624. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy Pc Critical pressure Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature Vc Critical volume ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions ΔvapS Entropy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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