Acetaldehyde

• Formula: C₂H₄O
• Molecular weight: 44.0526
• IUPAC Standard InChI: InChI=1S/C2H4O/c1-2-3/h2H,1H3 Copy

  
• IUPAC Standard InChIKey: IKHGUXGNUITLKF-UHFFFAOYSA-N Copy
• CAS Registry Number: 75-07-0
• 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: Acetic aldehyde; Ethanal; Ethyl aldehyde; CH3CHO; Acetaldehyd; Aldehyde acetique; Aldeide acetica; NCI-C56326; Octowy aldehyd; Acetylaldehyde; Rcra waste number U001; UN 1089; NSC 7594
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• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Gas Chromatography
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  • Gas Phase Kinetics Database
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Gas phase thermochemistry data

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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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

Constant pressure heat capacity of gas

Gas phase ion energetics data

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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 C₂H₄O⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₂H₃O^- +  =

By formula: C₂H₃O^- + H⁺ = C₂H₄O

C₂H₃O^- +  =

By formula: C₂H₃O^- + H⁺ = C₂H₄O

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• GAS (100 mmHg, N2 ADDED, TOTAL PRESSURE 600 mmHg); DOW KBr FOREPRISM-GRATING; DIGITIZED BY COBLENTZ SOCIETY (BATCH I) FROM HARD COPY; 2 cm^-1 resolution
• GAS (180 mmHg PRESSURE); Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution
• SOLUTION (10% CCl4 FOR 2.6-7.5, 10% CS2 FOR 7.5-22); DOW KBr FOREPRISM-GRATING $$SPECTRAL CONTAMINATION DUE TO CCl4 AROUND 1550 CM^-1 HAS BEEN SUBTRACTED; DIGITIZED BY COBLENTZ SOCIETY (BATCH I) FROM HARD COPY; 2 cm^-1 resolution

Vibrational and/or electronic energy levels

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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:   C_s     Symmetry Number σ = 1

Source: Shimanouchi, 1972

Notes

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, 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.

Wiberg, Crocker, et al., 1991
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Thermodynamics Research Center, 1997
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Pitzer K.S., 1949
Pitzer K.S., Jr., Thermodynamics and vibrational spectrum of acetaldehyde, J. Am. Chem. Soc., 1949, 71, 2842-2844. [all data]

Della Vedova C.O., 1991
Della Vedova C.O., Raman and infrared spectra and photochemical behavior of acetaldehyde isolated in matrixes, J. Raman Spectrosc., 1991, 22, 505-507. [all data]

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East A.L.L., Ab initio statistical thermodynamical models for the computation of third-law entropies, J. Chem. Phys., 1997, 106, 6655-6674. [all data]

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Chao J., Perfect gas thermodynamic properties of methanal, ethanal and their deuterated species, Thermochim. Acta, 1980, 41, 41-54. [all data]

Chao J., 1986
Chao J., Thermodynamic properties of key organic oxygen compounds in the carbon range C1 to C4. Part 2. Ideal gas properties, J. Phys. Chem. Ref. Data, 1986, 15, 1369-1436. [all data]

Coleman C.F., 1949
Coleman C.F., The heat capacity of organic vapors. V. Acetaldehyde, J. Am. Chem. Soc., 1949, 71, 2839-2841. [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]

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]

Traeger, 1985
Traeger, J.C., Heat of formation for the formyl cation by photoionization mass spectrometry, Int. J. Mass Spectrom. Ion Processes, 1985, 66, 271. [all data]

Traeger, McLouglin, et al., 1982
Traeger, J.C.; McLouglin, R.G.; Nicholson, A.J.C., Heat of formation for acetyl cation in the gas phase, J. Am. Chem. Soc., 1982, 104, 5318. [all data]

El-Sherbini, Allam, et al., 1981
El-Sherbini, T.M.; Allam, S.H.; Migahed, M.D.; Dawoud, A.M., Mass spectrometric investigation of aliphatic aldehydes, Z. Naturforsch. A:, 1981, 36, 1334. [all data]

Jochims, Lohr, et al., 1978
Jochims, H.-W.; Lohr, W.; Baumgartel, H., Photoionization mass spectrometry studies of deuterated acetaldehydes CH₃CDO and CD₃CHO, Chem. Phys. Lett., 1978, 54, 594. [all data]

Staley, Wieting, et al., 1977
Staley, R.H.; Wieting, R.D.; Beauchamp, J.L., Carbenium ion stabilities in the gas phase and solution. An ion cyclotron resonance study of bromide transfer reactions involving alkali ions, alkyl carbenium ions, acyl cations and cyclic halonium ions, J. Am. Chem. Soc., 1977, 99, 5964. [all data]

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Hernandez, R.; Masclet, P.; Mouvier, G., Spectroscopie de photoelectrons d'aldehydes et de cetones aliphatiques, J. Electron Spectrosc. Relat. Phenom., 1977, 10, 333. [all data]

Holmes, Terlouw, et al., 1976
Holmes, J.L.; Terlouw, J.K.; Lossing, F.P., The thermochemistry of C₂H₄O⁺ ions, J. Phys. Chem., 1976, 80, 2860. [all data]

Meeks, Arnett, et al., 1975
Meeks, J.L.; Arnett, J.F.; Larson, D.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls. Ionization assignments, Chem. Phys. Lett., 1975, 30, 190. [all data]

McGlynn and Meeks, 1975
McGlynn, S.P.; Meeks, J.L., Photoelectron spectra of carbonyls: Acetaldehyde, acetamide, biacetyl, pyruvic acid, methyl pyruvate and vamide, J. Electron Spectrosc. Relat. Phenom., 1975, 6, 269. [all data]

Warneck, 1974
Warneck, P., Heat of formation of the HCO radical, Z. Naturforsch. A:, 1974, 29, 350. [all data]

Tam, Yee, et al., 1974
Tam, W.-C.; Yee, D.; Brion, C.E., Photoelectron spectra of some aldehydes and ketones, J. Electron Spectrosc. Relat. Phenom., 1974, 4, 77. [all data]

Ogata, Kitayama, et al., 1974
Ogata, H.; Kitayama, J.; Koto, M.; Kojima, S.; Nihei, Y.; Kamada, H., Vacuum ultraviolet absorption and photoelectron spectra of aliphatic ketones, Bull. Chem. Soc. Jpn., 1974, 47, 958. [all data]

Krassig, Reinke, et al., 1974
Krassig, R.; Reinke, D.; Baumgartel, H., Photo-reaktionen kleiner organischer molekule II. Die photoionenspektren der Isomeren propylen-cyclopropan und acetaldehyd-athylenoxyd, Ber. Bunsen-Ges. Phys. Chem., 1974, 78, 425. [all data]

Knowles and Nicholson, 1974
Knowles, D.J.; Nicholson, A.J.C., Ionization energies of formic and acetic acid monomers, J. Chem. Phys., 1974, 60, 1180. [all data]

Chadwick and Katrib, 1974
Chadwick, D.; Katrib, A., Photoelectron spectra of acetaldehyde and acetyl halides, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 39. [all data]

Potapov and Sorokin, 1972
Potapov, V.K.; Sorokin, V.V., Kinetic energies of products of dissociative photoionization of molecules. I. Aliphatic ketones and alcohols, Khim. Vys. Energ., 1972, 6, 387. [all data]

Cocksey, Eland, et al., 1971
Cocksey, B.J.; Eland, J.H.D.; Danby, C.J., The effect of alkyl substitution on ionisation potential, J. Chem. Soc., 1971, (B), 790. [all data]

Matthews and Warneck, 1969
Matthews, C.S.; Warneck, P., Heats of formation of CHO⁺ and C₃H₃⁺ by photoionization, J. Chem. Phys. 5, 1969, 1, 854. [all data]

Dewar and Worley, 1969
Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. I. Ionization potentials of some organic molecules and their interpretation, J. Chem. Phys., 1969, 50, 654. [all data]

Potapov, Filyugina, et al., 1968
Potapov, V.K.; Filyugina, A.D.; Shigorin, D.N.; Ozerova, G.A., Photoionization of some compounds containing the carbonyl and amino groups, Dokl. Akad. Nauk SSSR, 1968, 180, 398, In original 352. [all data]

Vilesov, 1960
Vilesov, F.I., The photoionization of vapors of compounds whose molecules contain carbonyl groups, Dokl. Phys. Chem., 1960, 132, 521, In original 1332. [all data]

Hurzeler, Inghram, et al., 1958
Hurzeler, H.; Inghram, M.G.; Morrison, J.D., Photon impact studies of molecules using a mass spectrometer, J. Chem. Phys., 1958, 28, 76. [all data]

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [all data]

Vilesov and Terenin, 1957
Vilesov, F.I.; Terenin, A.N., The photoionization of the vapors of certain organic compounds, Dokl. Akad. Nauk SSSR, 1957, 115, 744, In original 539. [all data]

Walsh, 1946
Walsh, A.D., The absorption spectrum of acetaldehyde in the vacuum ultra-violet, Proc. Roy. Soc. (London), 1946, A185, 176. [all data]

Johnson, Powis, et al., 1982
Johnson, K.; Powis, I.; Danby, C.J., A photoelectron-photoion coincidence study of acetaldehyde and ethylene oxide molecular ions, Chem. Phys., 1982, 70, 329. [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]

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Benoit, F.M.; Harrison, A.G., Predictive value of proton affinity. Ionization energy correlations involving oxygenated molecules, J. Am. Chem. Soc., 1977, 99, 3980. [all data]

Rao, 1975
Rao, C.N.R., Lone-pair ionization bands of chromophores in the photoelectron spectra of organic molecules, Indian J. Chem., 1975, 13, 950. [all data]

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Kimura, K.; Katsumata, S.; Yamazaki, T.; Wakabayashi, H., UV photoelectron spectra and sum rule consideration; out-of-plane orbitals of unsaturated compounds with planar-skeleton structure, J. Electron Spectrosc. Relat. Phenom., 1975, 6, 41. [all data]

Bombach, Stadelmann, et al., 1981
Bombach, R.; Stadelmann, J.P.; Vogt, J., The fragmentation and isomerization of internal energy selected acetaldehyde molecular cations, Chem. Phys., 1981, 60, 293. [all data]

Haney and Franklin, 1969
Haney, M.A.; Franklin, J.L., Excess energies in mass spectra of some oxygen-containing organic compounds, J. Chem. Soc. Faraday Trans., 1969, 65, 1794. [all data]

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Shigorin, D.N.; Filyugina, A.D.; Potapov, V.K., Ionization and dissociation of molecules of acetaldehyde, acetone, and acetic acid on electron impact, Teor. i Eksperim. Khim., 1966, 2, 554, In original 417. [all data]

Dorman, 1965
Dorman, F.H., Fragment ions from CH₃CHO and (CH₃)₂CO by electron impact, J. Chem. Phys., 1965, 42, 65. [all data]

Burgers and Holmes, 1982
Burgers, P.C.; Holmes, J.L., Metastable ion studies. XIII. The measurement of appearance energies of metastable peaks, Org. Mass Spectrom., 1982, 17, 123. [all data]

Mead, Lykke, et al., 1984
Mead, R.D.; Lykke, K.R.; Lineberger, W.C.; Marks, J.; Brauman, J.I., Spectroscopy and Dynamics of the Dipole-Bound State of Acetaldehyde Enolate., J. Chem. Phys., 1984, 81, 11, 4883., https://doi.org/10.1063/1.447515 . [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]

Holmes and Lossing, 1982
Holmes, J.L.; Lossing, F.P., Heats of formation of the ionic and neutral enols of acetaldehyde and acetone, J. Am. Chem. Soc., 1982, 104, 2648. [all data]

Cumming and Kebarle, 1978
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Nimlos, M.R.; Soderquist, J.A.; Ellison, G.B., Spectroscopy of CH3CO- and CH3CO, J. Am. Chem. Soc., 1989, 111, 20, 7675, https://doi.org/10.1021/ja00202a001 . [all data]

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DePuy, C.H.; Bierbaum, V.M.; Damrauer, R.; Soderquist, J.A., Gas-phase reactions of the acetyl anion, J. Am. Chem. Soc., 1985, 107, 3385. [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]

Graul and Squires, 1988
Graul, S.T.; Squires, R.R., On the Existence of Alkyl Carbanions in the Gas Phase, J. Am. Chem. Soc., 1988, 110, 2, 607, https://doi.org/10.1021/ja00210a054 . [all data]

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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 thermochemistry data, Gas phase ion energetics data, IR Spectrum, Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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