Acetonitrile
- Formula: C2H3N
- Molecular weight: 41.0519
- IUPAC Standard InChIKey: WEVYAHXRMPXWCK-UHFFFAOYSA-N
- CAS Registry Number: 75-05-8
- 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: Cyanomethane; Ethanenitrile; Ethyl nitrile; Methane, cyano-; Methanecarbonitrile; Methyl cyanide; CH3CN; Acetonitril; Cyanure de methyl; USAF EK-488; Methylkyanid; NA 1648; NCI-C60822; Rcra waste number U003; UN 1648; Ethanonitrile
- Permanent link for this species. Use this link for bookmarking this species for future reference.
- Information on this page:
- Other data available:
- Gas phase thermochemistry data
- Condensed phase thermochemistry data
- Phase change data
- Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 100, reactions 101 to 150, reactions 151 to 188
- Henry's Law data
- Ion clustering data
- IR Spectrum
- Mass spectrum (electron ionization)
- UV/Visible spectrum
- Gas Chromatography
- Data at other public NIST sites:
- Options:
Data at NIST subscription sites:
- NIST / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
- NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)
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 ion energetics data
Go To: Top, 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
MM - Michael M. Meot-Ner (Mautner)
LL - Sharon G. Lias and Joel F. Liebman
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 C2H3N+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 12.20 ± 0.01 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 186.2 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 179. | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
0.01101 | EFD | Suess, Liu, et al., 2003 | B |
0.0030 ± 0.0072 | LPES | Bailey, Dessent, et al., 1996 | B |
0.01149 | EFD | Desfrancois, Abdoul-Carime, et al., 1994 | EA: 11.5 meV. Dipole-bound state.; B |
Proton affinity at 298K
Proton affinity (kcal/mol) | Reference | Comment |
---|---|---|
188.2 ± 1.4 | Williams, Denault, et al., 2001 | T = T(eff) = 498-797 KK; propionitrile, butyronitrile, valeronitrile reference compounds; MM |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
12.201 ± 0.002 | PE | Gochel-Dupuis, Delwiche, et al., 1992 | LL |
12.38 ± 0.04 | EI | Harland and McIntosh, 1985 | LBLHLM |
12.3 ± 0.25 | EI | Chess, Lapp, et al., 1982 | LBLHLM |
12.33 ± 0.08 | EI | Allam, Migahed, et al., 1982 | LBLHLM |
12.194 ± 0.005 | PI | Rider, Ray, et al., 1981 | LLK |
12.21 | PE | Kimura, Katsumata, et al., 1981 | LLK |
12.20 ± 0.01 | PE | Staley, Kleckner, et al., 1976 | LLK |
13.14 | PE | Lake and Thompson, 1970 | RDSH |
15.11 | PE | Lake and Thompson, 1970 | RDSH |
12.12 | PE | Frost, Herring, et al., 1970 | RDSH |
13.11 | PE | Frost, Herring, et al., 1970 | RDSH |
15.12 | PE | Frost, Herring, et al., 1970 | RDSH |
16.98 | PE | Frost, Herring, et al., 1970 | RDSH |
12.19 ± 0.01 | PI | Dibeler and Liston, 1968 | RDSH |
12.23 ± 0.05 | EI | Franklin, Wada, et al., 1966 | RDSH |
12.205 ± 0.004 | PI | Nicholson, 1965 | RDSH |
12.22 ± 0.01 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
12.46 | PE | Asbrink, Von Niessen, et al., 1980 | Vertical value; LLK |
12.20 | PE | Lake and Thompson, 1970 | Vertical value; RDSH |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C+ | 27.0 ± 0.3 | ? | EI | Reed and Snedden, 1956 | RDSH |
CH+ | 22.4 ± 0.2 | ? | EI | Reed and Snedden, 1956 | RDSH |
CH2+ | 15.7 | HCN | EI | Haney and Franklin, 1968 | RDSH |
CH2+ | 14.94 ± 0.02 | HCN | PI | Dibeler and Liston, 1968 | RDSH |
C2HN+ | 15.90 ± 0.08 | ? | EI | Harland and McIntosh, 1985 | LBLHLM |
C2HN+ | 15.1 ± 0.1 | H2 | PI | Dibeler and Liston, 1968 | RDSH |
C2H2N+ | 13.94 ± 0.02 | H | N/A | Holmes, Lossing, et al., 1993 | LL |
C2H2N+ | 14.38 ± 0.04 | H | EI | Harland and McIntosh, 1985 | LBLHLM |
C2H2N+ | 14.75 ± 0.08 | H | EI | Allam, Migahed, et al., 1982 | LBLHLM |
C2H2N+ | 14.01 ± 0.02 | H | PI | Dibeler and Liston, 1968 | RDSH |
C2H2N+ | 13.54 ± 0.08 | H | EI | Franklin, Wada, et al., 1966 | RDSH |
C2H2N+ | 14.28 ± 0.05 | H | EI | Pottie and Lossing, 1961 | RDSH |
C2N+ | 20.00 ± 0.08 | ? | EI | Harland and McIntosh, 1985 | LBLHLM |
De-protonation reactions
C2H2N- + =
By formula: C2H2N- + H+ = C2H3N
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 372.9 ± 2.1 | kcal/mol | G+TS | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 369.0 ± 4.5 | kcal/mol | CIDT | Graul and Squires, 1990 | gas phase; B |
ΔrH° | 373.3 ± 2.6 | kcal/mol | G+TS | Cumming and Kebarle, 1978 | gas phase; B |
ΔrH° | 374.8 ± 2.0 | kcal/mol | D-EA | Zimmerman and Brauman, 1977 | gas phase; B |
ΔrH° | 366.6 ± 4.6 | kcal/mol | EIAE | Heni and Illenberger, 1986 | gas phase; From MeCN; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 365.2 ± 2.0 | kcal/mol | IMRE | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrG° | 365.6 ± 2.0 | kcal/mol | IMRE | Cumming and Kebarle, 1978 | gas phase; B |
ΔrG° | 367.2 ± 2.1 | kcal/mol | H-TS | Zimmerman and Brauman, 1977 | gas phase; B |
Vibrational and/or electronic energy levels
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 by: Takehiko Shimanouchi
Symmetry: C3ν 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 | 2954 | A | 2954.1 M | gas | 2942 VS | liq. | ||
a1 | 2 | CN str | 2267 | A | 2266.5 M | gas | 2249 S | liq. | ||
a1 | 3 | CH3 s-deform | 1385 | C | 1376 M | liq. | OC(ν3+ν4) | |||
a1 | 4 | CC str | 920 | A | 920.2 S | gas | 918 S | liq. | ||
e | 5 | CH3 d-str | 3009 | A | 3009.2 S | gas | 2999 S | liq. | ||
e | 6 | CH3 d-deform | 1448 | D | 1447.9 S | gas | 1440 M b | liq. | FR(ν7+ν8) | |
e | 7 | CH3 rock | 1041 | A | 1040.8 M | gas | ||||
e | 8 | CCN bend | 362 | B | 362 S | gas | 380 S | liq. | ||
Source: Shimanouchi, 1972
Notes
VS | Very strong |
S | Strong |
M | Medium |
b | Broad |
FR | Fermi resonance with an overtone or a combination tone indicated in the parentheses. |
OC | Frequency estimated from an overtone or a combination tone indicated in the parentheses. |
A | 0~1 cm-1 uncertainty |
B | 1~3 cm-1 uncertainty |
C | 3~6 cm-1 uncertainty |
D | 6~15 cm-1 uncertainty |
References
Go To: Top, Gas phase ion energetics data, 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.
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]
Suess, Liu, et al., 2003
Suess, L.; Liu, Y.; Parthasarathy, R.; Dunning, F.B.,
Dipole-bound negative ions: Collisional destruction and blackbody-radiation-induced photodetachment,
J. Chem. Phys., 2003, 119, 24, 12890-12894, https://doi.org/10.1063/1.1628215
. [all data]
Bailey, Dessent, et al., 1996
Bailey, C.G.; Dessent, C.E.H.; Johnson, M.A.; Bowen, K.A., Jr.,
Vibronic Effects in the Photon Energy Dependent Photoelectron Spectra of the CH3CN- Dipole-bound Anion,
J. Chem. Phys., 1996, 104, 18, 6976, https://doi.org/10.1063/1.471415
. [all data]
Desfrancois, Abdoul-Carime, et al., 1994
Desfrancois, C.; Abdoul-Carime, H.; Khelifa, N.; Schermann, J.P.,
Fork 1/r to 1/r2 Potentials: Electron Exchange between Rydberg Atoms and Polar Molecules,
Phys. Rev. Lett., 1994, 73, 18, 2436, https://doi.org/10.1103/PhysRevLett.73.2436
. [all data]
Williams, Denault, et al., 2001
Williams, T.I.; Denault, J.W.; Cooks, R.G.,
Proton Affinity of Deuterated Acetonitrile Estimated by the Kinetic Method with Full Entropy Analysis,
Int. J. Mass Spectrom., 2001, 210/211, 133. [all data]
Gochel-Dupuis, Delwiche, et al., 1992
Gochel-Dupuis, M.; Delwiche, J.; Hubin-Franskin, M.-J.; Collin, J.E.,
High-resolution HeI photoelectron spectrum of acetonitrile,
Chem. Phys. Lett., 1992, 193, 41. [all data]
Harland and McIntosh, 1985
Harland, P.W.; McIntosh, B.J.,
Enthalpies of formation for the isomeric ions HxCCN+ and HxCNC+ (x = 0-3) by monochromatic electron impact on C2N2, CH3CN and CH3NC.,
Int. J. Mass Spectrom. Ion Processes, 1985, 67, 29. [all data]
Chess, Lapp, et al., 1982
Chess, E.K.; Lapp, R.L.; Gross, M.L.,
The question of tautomerism of alkylnitrile and isonitrile radical cations,
Org. Mass Spectrom., 1982, 17, 475. [all data]
Allam, Migahed, et al., 1982
Allam, S.H.; Migahed, M.D.; El-Khodary, A.,
Electron impact ionization and dissociation of deuterated and non-deuterated methanol, methyl cyanide, nitromethane and nitrobenzene,
Egypt. J. Phys., 1982, 13, 167. [all data]
Rider, Ray, et al., 1981
Rider, D.M.; Ray, G.W.; Darland, E.J.; Leroi, G.E.,
A photoionization mass spectrometric investigation of CH3CN and CD3CN,
J. Chem. Phys., 1981, 74, 1652. [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]
Staley, Kleckner, et al., 1976
Staley, R.H.; Kleckner, J.E.; Beauchamp, J.L.,
Relationship between orbital ionization energies and molecular properties. Proton affinities and photoelectron spectra of nitriles,
J. Am. Chem. Soc., 1976, 98, 2081. [all data]
Lake and Thompson, 1970
Lake, R.F.; Thompson, H.,
The photoelectron spectra of some molecules containing the C N group,
Proc. Roy. Soc. (London), 1970, A317, 187. [all data]
Frost, Herring, et al., 1970
Frost, D.C.; Herring, F.G.; McDowell, C.A.; Stenhouse, I.A.,
The ionization potentials of methyl cyanide and methyl acetylene by photoelectron spectroscopy and semi-rigorous LCAO SCF calculations,
Chem. Phys. Lett., 1970, 4, 533. [all data]
Dibeler and Liston, 1968
Dibeler, V.H.; Liston, S.K.,
Mass-spectrometric study of photoionization. IX. Hydrogen cyanide and acetonitrile,
J. Chem. Phys., 1968, 48, 4765. [all data]
Franklin, Wada, et al., 1966
Franklin, J.L.; Wada, Y.; Natalis, P.; Hierl, P.M.,
Ion-molecule reactions in acetonitrile and propionitrile,
J. Phys. Chem., 1966, 70, 2353. [all data]
Nicholson, 1965
Nicholson, A.J.C.,
Photoionization-efficiency curves. II. False and genuine structure,
J. Chem. Phys., 1965, 43, 1171. [all data]
Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J.,
Ionization potentials of some molecules,
J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]
Asbrink, Von Niessen, et al., 1980
Asbrink, L.; Von Niessen, W.; Bieri, G.,
30.4-nm He(II) photoelectron spectra of organic molecules,
J. Electron Spectrosc. Relat. Phenom., 1980, 21, 93. [all data]
Reed and Snedden, 1956
Reed, R.I.; Snedden, W.,
Studies in electron impact methods. Part 6.-The formation of the methine and carbon ions,
J. Chem. Soc. Faraday Trans., 1956, 55, 876. [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]
Holmes, Lossing, et al., 1993
Holmes, J.L.; Lossing, F.P.; Mayer, P.M.,
The effects of methyl substitution on the structure and thermochemistry of the cyanomethyl radical and cation,
Chem. Phys. Lett., 1993, 212, 134. [all data]
Pottie and Lossing, 1961
Pottie, R.F.; Lossing, F.P.,
Free radicals by mass spectrometry. XXV. Ionization potentials of cyanoalkyl radicals,
J. Am. Chem. Soc., 1961, 83, 4737. [all data]
Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr.,
The gas phase acidity scale from methanol to phenol,
J. Am. Chem. Soc., 1979, 101, 6047. [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]
Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P.,
Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A),
Can. J. Chem., 1978, 56, 1. [all data]
Zimmerman and Brauman, 1977
Zimmerman, A.H.; Brauman, J.I.,
Electron photodetachment from negative ions of C2v symmetry. Electron affinities of allyl and cyanomethyl radicals,
J. Am. Chem. Soc., 1977, 99, 3565. [all data]
Heni and Illenberger, 1986
Heni, M.; Illenberger, E.,
Electron attachment by saturated nitriles. Acrylonitrile (CH2H3CN), and benzonitrile (C6H5CN),
Int. J. Mass Spectrom. Ion Phys., 1986, 73, 127. [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 ion energetics data, Vibrational and/or electronic energy levels, References
- Symbols used in this document:
AE Appearance energy EA Electron affinity IE (evaluated) Recommended ionization energy ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy 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.