Acetylene
- Formula: C2H2
- Molecular weight: 26.0373
- IUPAC Standard InChIKey: HSFWRNGVRCDJHI-UHFFFAOYSA-N
- CAS Registry Number: 74-86-2
- 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: Ethyne; Ethine; Narcylen; C2H2; Acetylen; UN 1001; Vinylene
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Gas phase ion energetics data
Go To: Top, 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
LL - Sharon G. Lias and Joel F. Liebman
View reactions leading to C2H2+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 11.400 ± 0.002 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 641.4 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 616.7 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
Appearance energy determinations
De-protonation reactions
C2H- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1580. ± 20. | kJ/mol | AVG | N/A | Average of 8 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1550. ± 20. | kJ/mol | AVG | N/A | Average of 7 values; Individual data points |
References
Go To: Top, 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.
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]
Plessis and Marmet, 1986
Plessis, P.; Marmet, P.,
Electroionization study of acetylene and fragment ions,
Int. J. Mass Spectrom. Ion Processes, 1986, 70, 23. [all data]
Hayaishi, Iwata, et al., 1982
Hayaishi, T.; Iwata, S.; Sasanuma, M.; Ishiguro, E.; Morioka, Y.; Iida, Y.; Nakamura, M.,
Photoionisation mass spectrometric study of acetylene in the VUV region,
J. Phys. B:, 1982, 15, 79. [all data]
Rosmus, Botschwina, et al., 1981
Rosmus, P.; Botschwina, P.; Maier, J.P.,
On the ionic states of vinylidene and acetylene,
Chem. Phys. Lett., 1981, 84, 71. [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, Schmelzer, et al., 1980
Bieri, G.; Schmelzer, A.; Asbrink, L.; Jonsson, M.,
Fluorine and the fluoroderivatives of acetylene and diacetylene studied by 30.4 nm He(II) photoelectron spectroscopy,
Chem. Phys., 1980, 49, 213. [all data]
Suzuki and Maeda, 1978
Suzuki, I.H.; Maeda, K.,
Ionization efficiency curves of acetylene by mono-energetic electron impact,
Adv. Mass Spectrom., 1978, 7, 182. [all data]
Suzuki and Maeda, 1977
Suzuki, I.H.; Maeda, K.,
Ionization efficiency curves of acetylene by electron impact,
Mass Spectrosc. (Tokyo), 1977, 25, 223. [all data]
Bieri, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P.,
Valence ionization enrgies of hydrocarbons,
Helv. Chim. Acta, 1977, 60, 2213. [all data]
Van Veen and Plantenga, 1976
Van Veen, E.H.; Plantenga, F.L.,
Low-energy electron-impact excitation spectra of acetylene,
Chem. Phys. Lett., 1976, 38, 493. [all data]
Reeher, Flesch, et al., 1976
Reeher, J.R.; Flesch, G.D.; Svec, H.J.,
The mass spectra and ionization potentials of the neutral fragments produced during the electron bombardment of aromatic compounds,
Org. Mass Spectrom., 1976, 11, 154. [all data]
Carlier, Dubois, et al., 1975
Carlier, P.; Dubois, J.E.; Masclet, P.; Mouvier, G.,
Spectres de photoelectrons des alcynes,
J. Electron Spectrosc. Relat. Phenom., 1975, 7, 55. [all data]
Parr and Taylor, 1973
Parr, G.R.; Taylor, J.W.,
A photoionization mass spectrometer utilizing a high intensity molecular beam sampling system and synchrotron radiation,
Rev. Sci. Instrum., 1973, 44, 1578. [all data]
Dibeler and Walker, 1973
Dibeler, V.H.; Walker, J.A.,
Photoionization of acetylene near threshold,
Int. J. Mass Spectrom. Ion Phys., 1973, 11, 49. [all data]
Brogli, Heilbronner, et al., 1973
Brogli, F.; Heilbronner, E.; Hornung, V.; Kloster-Jensen, E.,
230. Die photoelektronen-spektren methyl-substituierter Acetylene,
Helv. Chim. Acta, 1973, 56, 2171. [all data]
Lossing, 1970
Lossing, F.P.,
Threshold ionization of acetylene by monoenergetic electron impact,
Intern. J. Mass Spectrom. Ion Phys., 1970, 5, 190. [all data]
Omura, Kaneko, et al., 1969
Omura, I.; Kaneko, T.; Yamada, Y.; Tanaka, K.,
Mass spectrometric studies of photoionization. IV. Acetylene and propyne,
J. Phys. Soc. Japan, 1969, 27, 178. [all data]
Williams and Hamill, 1968
Williams, J.M.; Hamill, W.H.,
Ionization potentials of molecules and free radicals and appearance potentials by electron impact in the mass spectrometer,
J. Chem. Phys., 1968, 49, 4467. [all data]
Collins, Winters, et al., 1968
Collins, J.H.; Winters, R.E.; Engerholm, G.G.,
Fine structure in energy-distribution-difference ionizationefficiency curves,
J. Chem. Phys., 1968, 49, 2469. [all data]
Baker and Turner, 1968
Baker, C.; Turner, D.W.,
High resolution molecular photoelectron spectroscopy. III.Acetylenes and azaacetylenes,
Proc. Roy. Soc. (London), 1968, A308, 19. [all data]
Brehm, 1966
Brehm, B.,
Massenspektrometrische Untersuchung der Photoionisation von Molekulen,
Z. Naturforsch., 1966, 21a, 196. [all data]
Nicholson, 1965
Nicholson, A.J.C.,
Photoionization-efficiency curves. II. False and genuine structure,
J. Chem. Phys., 1965, 43, 1171. [all data]
Melton and Hamill, 1964
Melton, C.E.; Hamill, W.H.,
Appearance potentials by the retarding potential-difference method for secondary ions produced by excited-neutral, excited ion-neutral, and ion-neutral reactions,
J. Chem. Phys., 1964, 41, 1469. [all data]
Dibeler and Reese, 1964
Dibeler, V.H.; Reese, R.M.,
Mass spectrometric study of photoionization. I. Apparatus and initial observations on acetylene, acetylene-d2, benzene, and benzene-d6,
J. Res. NBS, 1964, 68A, 409. [all data]
Watanabe and Namioka, 1956
Watanabe, K.; Namioka, T.,
Ionization potential of propyne,
J. Chem. Phys., 1956, 24, 915. [all data]
Kusch, Hustrulid, et al., 1937
Kusch, P.; Hustrulid, A.; Tate, J.T.,
The dissociation of HCN, C2H2, C2N2 and C2H4 by electron impact,
Phys. Rev., 1937, 52, 843. [all data]
Price, 1935
Price, W.C.,
The absorption spectra of acetylene, ethylene, and ethane in the far ultraviolet,
Phys. Rev., 1935, 47, 444. [all data]
Bieri and Asbrink, 1980
Bieri, G.; Asbrink, L.,
30.4-nm He(II) photoelectron spectra of organic molecules,
J. Electron Spectrosc. Relat. Phenom., 1980, 20, 149. [all data]
Cavell and Allison, 1978
Cavell, R.G.; Allison, D.A.,
Photoelectron spectra of acetylene with He(I), He(II) , Zr M175»{zeta}, MgK»α radiation sources,
J. Chem. Phys., 1978, 69, 159. [all data]
Locht and Davister, 1995
Locht, R.; Davister, M.,
The dissociative ionization of C2H2. The C+, C2+, and CH2+ dissociation channels. The vinylidene ion as a transient?,
Chem. Phys., 1995, 195, 443. [all data]
Cooper, Ibuki, et al., 1988
Cooper, G.; Ibuki, T.; Iida, Y.; Brion, C.E.,
Absolute dipole oscillator strengths for photoabsorption and the molecular and dissociative photoionization of acetylene,
Chem. Phys., 1988, 125, 307. [all data]
Bloch, 1963
Bloch, A.,
Mass spectra of acetylene under high pressure in the ion source,
Advan. Mass Spectrom., 1963, 2, 48. [all data]
Davister and Locht, 1995
Davister, M.; Locht, R.,
The dissociative ionization of C2H2 and C2D2. The [CH(CD)]+ dissociation channel. The H(D)C≡C(D)H binding energy,
Chem. Phys., 1995, 191, 333. [all data]
Kloster-Jensen, Pascual, et al., 1970
Kloster-Jensen, E.; Pascual, C.; Vogt, J.,
Mass spectrometric studies of mono- and di-haloacetylenes,,
Helv. Chim. Acta, 1970, 53, 2109. [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]
Franklin and Munson, 1965
Franklin, J.L.; Munson, M.S.B.,
Ion-molecule reactions in methane-oxygen and acetylene-oxygen systems,
Symp. Combust., 10th, Univ. Cambridge, Cambridge, Engl.,, 1965, 1964, 561. [all data]
Reid, Ballantine, et al., 1995
Reid, C.J.; Ballantine, J.A.; Andrews, S.R.; Harris, F.M.,
Charge inversion of ground-state and metastable-state C2+ cations formed from electroionised C2H2 and C2N2, and a re-evaluation of the carbon dimer's ionisation energy,
Chem. Phys., 1995, 190, 113. [all data]
Momigny and Derouane, 1968
Momigny, J.; Derouane, E.,
Fine structure in the first derivative of ionization curves obtained under electron impact,
Advan. Mass Spectrom., 1968, 4, 607. [all data]
Field, Franklin, et al., 1957
Field, F.H.; Franklin, J.L.; Lampe, F.W.,
Reactions of gaseous ions. II. Acetylene,
J. Am. Chem. Soc., 1957, 79, 2665. [all data]
Coats and Anderson, 1957
Coats, F.H.; Anderson, R.C.,
Thermodynamic data from electron-impact measurements on acetylene and substituted acetylenes,
J. Am. Chem. Soc., 1957, 79, 1340. [all data]
Servais and Locht, 1995
Servais, C.; Locht, R.,
The appearance energy of C2H+ from C2H2 revisited. A photoion-photoelectron coincidence spectroscopic determination,
Chem. Phys. Lett., 1995, 236, 96. [all data]
Weitzel, Mahnert, et al., 1994
Weitzel, K.-M.; Mahnert, J.; Penno, M.,
ZEKE-PEPICO investigations of dissociation energies in ionic reactions,
Chem. Phys. Lett., 1994, 224, 371. [all data]
Davister and Locht, 1994
Davister, M.; Locht, R.,
The dissociative electroionization of C2H2, C2D2 and C2HD. Investigation of the [C2H(D)]+ and [H(D)]+ dissociation channels. The (D)H-C2H(D) binding energy,
Chem. Phys., 1994, 189, 805. [all data]
Norwood and Ng, 1989
Norwood, K.; Ng, C.Y.,
A state-selected study of the unimolecular decompoisition of C2H2+(A,B) using the photoion photoelectron coincidence method,
J. Chem. Phys., 1989, 91, 2898. [all data]
Ono and Ng, 1981
Ono, Y.; Ng, C.Y.,
The heat of formation of C2H+,
J. Chem. Phys., 1981, 74, 6985. [all data]
Eland, 1979
Eland, J.H.D.,
Dissociations of state-selected C2H2+, H2S+ and D2S+ ions studied by photoelectron-photoion coincidence spectroscopy,
Int. J. Mass Spectrom. Ion Phys., 1979, 31, 161. [all data]
Dibeler, Walker, et al., 1973
Dibeler, V.H.; Walker, J.A.; McCulloh, K.E.,
Observations on hot bands in the molecular and dissociative photoionization of acetylene and the heat of formation of the ethynyl ion,
J. Chem. Phys., 1973, 59, 2264. [all data]
Botter, Dibeler, et al., 1966
Botter, R.; Dibeler, V.H.; Walker, J.A.; Rosenstock, H.M.,
Experimental and theoretical studies of photoionization-efficiency curves for C2H2 and C2D2,
J. Chem. Phys., 1966, 44, 1271. [all data]
Shiromaru, Achiba, et al., 1987
Shiromaru, H.; Achiba, Y.; Kimura, K.; Lee, Y.T.,
Determination of the C-H bond dissociation energies of ethylene and acetylene by observation of the threshold energies of H+ formation by synchrotron radiation,
J. Phys. Chem., 1987, 91, 17. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy 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
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