Acetylene

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Gas phase 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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas54.190kcal/molReviewChase, 1998Data last reviewed in March, 1961
Δfgas54.3 ± 0.2kcal/molReviewManion, 2002adopted recommendation of Gurvich, Veyts, et al., 1991; DRB
Δfgas54.19 ± 0.19kcal/molCcbWagman, Kilpatrick, et al., 1945Unpublished work of E. J. Prosen; ALS
Quantity Value Units Method Reference Comment
gas,1 bar48.023cal/mol*KReviewChase, 1998Data last reviewed in March, 1961

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
7.015100.Gurvich, Veyts, et al., 1989p=1 bar.; GT
8.501200.
10.53298.15
10.56300.
12.04400.
13.09500.
13.89600.
14.57700.
15.18800.
15.73900.
16.241000.
16.711100.
17.131200.
17.521300.
17.871400.
18.181500.
18.471600.
18.731700.
18.961800.
19.171900.
19.362000.
19.542100.
19.702200.
19.842300.
19.982400.
20.112500.
20.222600.
20.332700.
20.432800.
20.532900.
20.623000.

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.

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View table.

Temperature (K) 298. to 1100.1100. to 6000.
A 9.72442016.12630
B 9.7353712.808581
C -3.866731-0.483143
D 0.8770890.032551
E -0.157364-2.343790
F 50.3601144.32481
G 56.1675960.59601
H 54.1901154.19011
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in March, 1961 Data last reviewed in March, 1961

Gas phase ion energetics data

Go To: Top, Gas phase 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 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 ± 0.002eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)153.3kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity147.4kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
11.41 ± 0.01EIPlessis and Marmet, 1986LBLHLM
11.40PIHayaishi, Iwata, et al., 1982LBLHLM
11.4EVALRosmus, Botschwina, et al., 1981LLK
11.40PEKimura, Katsumata, et al., 1981LLK
11.40PEBieri, Schmelzer, et al., 1980LLK
11.4 ± 0.1EISuzuki and Maeda, 1978LLK
11.4 ± 0.1EISuzuki and Maeda, 1977LLK
11.40 ± 0.02PEBieri, Burger, et al., 1977LLK
~11.3EIVan Veen and Plantenga, 1976LLK
11.37 ± 0.05EIReeher, Flesch, et al., 1976LLK
11.403 ± 0.0003PECarlier, Dubois, et al., 1975LLK
11.394 ± 0.005PIParr and Taylor, 1973LLK
11.398 ± 0.005PIDibeler and Walker, 1973LLK
11.40PEBrogli, Heilbronner, et al., 1973LLK
11.39 ± 0.02EILossing, 1970RDSH
11.395 ± 0.015PIOmura, Kaneko, et al., 1969RDSH
11.39 ± 0.05EIWilliams and Hamill, 1968RDSH
11.41 ± 0.01EICollins, Winters, et al., 1968RDSH
11.40 ± 0.01PEBaker and Turner, 1968RDSH
11.400 ± 0.005PIBrehm, 1966RDSH
11.396 ± 0.003PINicholson, 1965RDSH
11.40 ± 0.02EIMelton and Hamill, 1964RDSH
11.406 ± 0.006PIDibeler and Reese, 1964RDSH
11.41 ± 0.01PIWatanabe and Namioka, 1956RDSH
11.2 ± 0.1EIKusch, Hustrulid, et al., 1937RDSH
11.41SPrice, 1935RDSH
11.49PEBieri and Asbrink, 1980Vertical value; LLK
11.43PECavell and Allison, 1978Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C+21.20 ± 0.05CH2EILocht and Davister, 1995LL
C+24. ± 1.?PICooper, Ibuki, et al., 1988LL
C+20.43 ± 0.05CH2EIPlessis and Marmet, 1986LBLHLM
C+22.5 ± 0.3C+2HEISuzuki and Maeda, 1977LLK
C+23.6?EIBloch, 1963RDSH
C+24.5 ± 1.0C+2HEIKusch, Hustrulid, et al., 1937RDSH
CH+20.85 ± 0.05CHEIDavister and Locht, 1995LL
CH+20.54 ± 0.05CHEIPlessis and Marmet, 1986LBLHLM
CH+23.9 ± 0.2C+HEIPlessis and Marmet, 1986LBLHLM
CH+24.1C+HPIHayaishi, Iwata, et al., 1982LBLHLM
CH+20.7 ± 0.1CHPIHayaishi, Iwata, et al., 1982LBLHLM
CH+20.9 ± 0.2CHEISuzuki and Maeda, 1977LLK
CH+21.5 ± 0.2CHEIKloster-Jensen, Pascual, et al., 1970RDSH
CH+21.9CHEIHaney and Franklin, 1968RDSH
CH+22.2 ± 0.5CHEIKusch, Hustrulid, et al., 1937RDSH
CH2+19.74 ± 0.20CEILocht and Davister, 1995LL
CH2+18.17 ± 0.09C-EIPlessis and Marmet, 1986LBLHLM
CH2+19.40 ± 0.12CEIPlessis and Marmet, 1986LBLHLM
CH2+19.4 ± 0.1CPIHayaishi, Iwata, et al., 1982LBLHLM
CH2+20.5 ± 0.2?EISuzuki and Maeda, 1977LLK
CH2+21.CEIFranklin and Munson, 1965RDSH
C2+19. ± 1.H2CIELReid, Ballantine, et al., 1995LL
C2+18.44 ± 0.07H2EILocht and Davister, 1995LL
C2+22.60 ± 0.122HEIPlessis and Marmet, 1986LBLHLM
C2+18.16 ± 0.05H2EIPlessis and Marmet, 1986LBLHLM
C2+18.1 ± 0.1H2PIHayaishi, Iwata, et al., 1982LBLHLM
C2+22.7 ± 0.12HPIHayaishi, Iwata, et al., 1982LBLHLM
C2+19.2 ± 0.2?EISuzuki and Maeda, 1977LLK
C2+23.62H?EIMomigny and Derouane, 1968RDSH
C2+19.5H2EIBloch, 1963RDSH
C2+23.82H?EIBloch, 1963RDSH
C2+22.72H?EIField, Franklin, et al., 1957RDSH
C2+18.2H2EIField, Franklin, et al., 1957RDSH
C2+23.3 ± 0.52H?EICoats and Anderson, 1957RDSH
C2+23.8 ± 0.32HEIKusch, Hustrulid, et al., 1937RDSH
C2H+17.35 ± 0.04HPIPECOServais and Locht, 1995LL
C2H+17.360HPIPECOWeitzel, Mahnert, et al., 1994LL
C2H+17.30 ± 0.08HEIDavister and Locht, 1994LL
C2H+17.33 ± 0.05HPIPECONorwood and Ng, 1989LL
C2H+16.70 ± 0.10HEIPlessis and Marmet, 1986LBLHLM
C2H+16.8 ± 0.1HPIHayaishi, Iwata, et al., 1982LBLHLM
C2H+16.79 ± 0.03HPIOno and Ng, 1981LLK
C2H+17.3HPIPECOEland, 1979LLK
C2H+17.5 ± 0.1HEISuzuki and Maeda, 1977LLK
C2H+17.36 ± 0.01HPIDibeler, Walker, et al., 1973LLK
C2H+17.22HPIBotter, Dibeler, et al., 1966RDSH
C2H+17.3HEIField, Franklin, et al., 1957RDSH
C2H+17.8 ± 0.2HEIKusch, Hustrulid, et al., 1937RDSH
H+18.83 ± 0.23C2HEIDavister and Locht, 1994LL
H+23. ± 1.?PICooper, Ibuki, et al., 1988LL
H+19.35 ± 0.05C2HPIShiromaru, Achiba, et al., 1987LBLHLM
H+20.6 ± 0.3?EISuzuki and Maeda, 1977LLK
H+21.7 ± 1.0C2+HEIKusch, Hustrulid, et al., 1937RDSH
H+25.6 ± 1.0CH+CEIKusch, Hustrulid, et al., 1937RDSH

De-protonation reactions

C2H- + Hydrogen cation = Acetylene

By formula: C2H- + H+ = C2H2

Quantity Value Units Method Reference Comment
Δr379. ± 5.kcal/molAVGN/AAverage of 8 values; Individual data points
Quantity Value Units Method Reference Comment
Δr370. ± 5.kcal/molAVGN/AAverage of 7 values; Individual data points

References

Go To: Top, Gas phase 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.

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Manion, 2002
Manion, J.A., Evaluated Enthalpies of Formation of the Stable Closed Shell C1 and C2 Chlorinated Hydrocarbons, J. Phys. Chem. Ref. Data, 2002, 31, 1, 123-172, https://doi.org/10.1063/1.1420703 . [all data]

Gurvich, Veyts, et al., 1991
Thermodynamic Properties of Individual Substances, 4th edition, Volume 2, Gurvich, L.V.; Veyts, I.V.; Alcock, C.B.;, ed(s)., Hemisphere, New York, 1991. [all data]

Wagman, Kilpatrick, et al., 1945
Wagman, D.D.; Kilpatrick, J.E.; Pitzer, K.S.; Rossini, F.D., Heats, equilibrium constants, and free energies of formation of the acetylene hydrocarbons through the pentynes, to 1,500° K, J. Res. NBS, 1945, 35, 467-496. [all data]

Gurvich, Veyts, et al., 1989
Gurvich, L.V.; Veyts, I.V.; Alcock, C.B., Thermodynamic Properties of Individual Substances, 4th ed.; Vols. 1 and 2, Hemisphere, New York, 1989. [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]

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 thermochemistry data, Gas phase ion energetics data, References