Formaldehyde

• Formula: CH₂O
• Molecular weight: 30.0260
• IUPAC Standard InChI: InChI=1S/CH2O/c1-2/h1H2 Copy

  
• IUPAC Standard InChIKey: WSFSSNUMVMOOMR-UHFFFAOYSA-N Copy
• CAS Registry Number: 50-00-0
• 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.
• Isotopologues:
  • methanal-d
• Other names: Methanal; BFV; Fannoform; Formaldehyde, gas; Formalin; Formalith; Formic aldehyde; Formol; Fyde; Lysoform; Methyl aldehyde; Methylene oxide; Morbicid; Oxomethane; Oxymethylene; Paraform; Superlysoform; Karsan; Methaldehyde; Aldehyde formique; Aldeide formica; Formaldehyd; Formalin-loesungen; Formalina; Formaline; NCI-C02799; Oplossingen; Aldehyd mravenci; Formalin 40; Rcra waste number U122; UN 1198; UN 2209; H2CO; Durine; Hercules 37M6-8; CH2O; NSC 298885; Fordor
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • Ion clustering data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
• Options:
  • Switch to SI units

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)

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Phase change 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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Enthalpy of fusion

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
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 CH₂O⁺ (ion structure unspecified)

Proton affinity at 298K

Gas basicity at 298K

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

CHO^- +  =

By formula: CHO^- + H⁺ = CH₂O

Ion clustering 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:
RCD - Robert C. Dunbar
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

 +  = ( • )

By formula: Al⁺ + CH₂O = (Al⁺ • CH₂O)

CH₂N⁺ +  = (CH₂N⁺ • )

By formula: CH₂N⁺ + CH₂O = (CH₂N⁺ • CH₂O)

Bond type: Hydrogen bonds of the type NH+-O between organics

 +  = ( • )

By formula: CH₃O⁺ + CH₂O = (CH₃O⁺ • CH₂O)

Bond type: Hydrogen bonds of the type OH-O between organics

(CH₃O^- • 4294967295) +  = CH₃O^-

By formula: (CH₃O^- • 4294967295CH₂O) + CH₂O = CH₃O^-

 +  = ( • )

By formula: Fe⁺ + CH₂O = (Fe⁺ • CH₂O)

( • ) +  = ( • 2)

By formula: (Fe⁺ • CH₂O) + CH₂O = (Fe⁺ • 2CH₂O)

( • 2) +  = ( • 3)

By formula: (Fe⁺ • 2CH₂O) + CH₂O = (Fe⁺ • 3CH₂O)

( • 3) +  = ( • 4)

By formula: (Fe⁺ • 3CH₂O) + CH₂O = (Fe⁺ • 4CH₂O)

 +  = ( • )

By formula: Li⁺ + CH₂O = (Li⁺ • CH₂O)

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_2ν     Symmetry Number σ = 2

Source: Shimanouchi, 1972

Notes

References

Go To: Top, Phase change data, Gas phase ion energetics data, Ion clustering 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.

Spence and Wild, 1935
Spence, R.; Wild, W., The Vapor Pressure Curve of Formaldehyde and Some Related Data, J. Chem. Soc., 1935, 1935, 506-9. [all data]

Anonymous, 1958
Anonymous, R., , Am. Pet. Inst. Res. Proj. 45, Ohio State Univ., 1958. [all data]

Harries, 1901
Harries, C.D., Chem. Ber., 1901, 34, 635. [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]

Spence and Wild, 1935, 2
Spence, Robert; Wild, William, 114. The vapour-pressure curve of formaldehyde, and some related data, J. Chem. Soc., 1935, 506, https://doi.org/10.1039/jr9350000506 . [all data]

Spence and Wild, 1935, 3
Spence, R.; Wild, W., The Vapour-Pressure Curve of Formaldehyde, and Some Related Data, J. Chem. Soc., 1935, 138, 506-509, https://doi.org/10.1039/jr9350000506 . [all data]

Vasil'ev and Lebedev, 1998
Vasil'ev, V.G.; Lebedev, B.V., Thermodynamic Properties of Aliphatic Aldehydes and Polyaldehydes: Effect of Composition and Structure, Polym. Sci., Ser. A, 1998, 40, 5, 464. [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]

Bouchoux and Leblanc, 2000
Bouchoux, G.; Leblanc, D., Gas-phase basicity of formaldehyde by the thermokinetic method, European J. Mass Spectrom., 2000, 6, 443. [all data]

Ohno, Okamura, et al., 1995
Ohno, K.; Okamura, K.; Yamakado, H.; Hoshino, S.; Takami, T.; Yamauchi, M., Penning ionization of HCHO, CH₂CH₂, and CH₂CHCHO by collision with He*(2 3S) metastable atoms, J. Phys. Chem., 1995, 99, 14247. [all data]

Niu, Shirley, et al., 1993
Niu, B.; Shirley, D.A.; Bai, Y., High resolution photoelectron spectroscopy and femtosecond intramolecular dynamics of H₂CO⁺ and D₂CO⁺, J. Chem. Phys., 1993, 98, 4377. [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]

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]

Von Niessen, Bieri, et al., 1980
Von Niessen, W.; Bieri, G.; Asbrink, L., 30.4 nm He(II) photoelectron spectra of organic molecules. Part III. Oxo-compounds (C,H,O), J. Electron Spectrosc. Relat. Phenom., 1980, 21, 175. [all data]

Hernandez, Masclet, et al., 1977
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]

Drury-Lessard and Moule, 1977
Drury-Lessard, C.R.; Moule, D.C., The higher Rydberg states of formaldehyde, Chem. Phys. Lett., 1977, 47, 300. [all data]

Guyon, Chupka, et al., 1976
Guyon, P.M.; Chupka, W.A.; Berkowitz, J., Photoionization mass spectrometric study of formaldehyde H₂CO, HDCO, and D₂CO, J. Chem. Phys., 1976, 65, 1419. [all data]

Warneck, 1971
Warneck, P., Photoionisation von methanol und formaldehyd, Z. Naturforsch. A:, 1971, 26, 2047. [all data]

Mentall, Gentieu, et al., 1971
Mentall, J.E.; Gentieu, E.P.; Krauss, M.; Neumann, D., Photoionization and absorption spectrum of formaldehyde in the vacuum ultraviolet, J. Chem. Phys., 1971, 55, 5471. [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]

Baker, Baker, et al., 1968
Baker, A.D.; Baker, C.; Brundle, C.R.; Turner, D.W., The electronic structures of methane, ethane, ethylene and formaldehyde studied by high-resolution molecular photoelectron spectroscopy, Intern. J. Mass Spectrom. Ion Phys., 1968, 1, 285. [all data]

Kanomata, 1961
Kanomata, I., Mass-spectrometric study on ionization and dissociation of formaldehyde, acetaldehyde, acetone and ethyl methyl ketone by electron impact, Bull. Chem. Soc. Japan, 1961, 34, 1864. [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]

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

Price, 1935
Price, W.C., The far ultraviolet absorption spectra of formaldehyde and the alkyl derivatives of H, O and H₂S, J. Chem. Phys., 1935, 3, 256. [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]

Wankenne, Caprace, et al., 1984
Wankenne, H.; Caprace, G.; Momigny, J., Unimolecular decay of metastable ions in formaldehyde, Int. J. Mass Spectrom. Ion Processes, 1984, 57, 149. [all data]

Brand and Reed, 1957
Brand, J.C.D.; Reed, R.I., The electronic spectrum of formaldehyde. Part II. Mechanisms of dissociation of formaldehyde and the formaldehyde molecular ion, J. Chem. Soc., 1957, 2386. [all data]

Murray, Miller, et al., 1986
Murray, K.K.; Miller, T.M.; Leopold, D.G.; Lineberger, W.C., Laser photoelectron spectroscopy of the Formylf anion, J. Chem. Phys., 1986, 84, 2520. [all data]

Karpas and Klein, 1975
Karpas, Z.; Klein, F.S., Negative ion-molecule reactions in a mixture of ammonia-formaldehyde - an ICR mass spectrometry study, Int. J. Mass Spectrom. Ion Phys., 1975, 18, 65. [all data]

Bouchard, Brenner, et al., 1997
Bouchard, F.; Brenner, V.; Carra, C.; Hepburn, J.W.; Koyanagi, G.K.; McMahon, T.B.; Ohanessian, G.; Peschke, M., Energetics and Structure of Complexes of Al+ with Small Organic Molecules in the Gas Phase, J. Phys. Chem. A, 1997, 101, 33, 5885, https://doi.org/10.1021/jp9703465 . [all data]

Tanaka, Mackay, et al., 1978
Tanaka, K.; Mackay, G.I.; Bohme, D.K., Rate and Equilibrium Constant Measurements for Gas-Phase Proton-Transfer Reactions Involving H2O, H2S, HCN, and H2CO, Can. J. Chem., 1978, 56, 2, 193, https://doi.org/10.1139/v78-031 . [all data]

Meot-Ner (Mautner), 1978
Meot-Ner (Mautner), M., Solvation of the Proton by HCN and CH3CN. Condensation of HCN with Ions in the Gas Phase., J. Am. Chem. Soc., 1978, 100, 15, 4694, https://doi.org/10.1021/ja00483a012 . [all data]

Larson and McMahon, 1982
Larson, J.W.; McMahon, T.B., Formation, Thermochemistry, and Relative Stabilities of Proton - Bound dimers of Oxygen n - Donor Bases from Ion Cyclotron Resonance Solvent - Exchange Equilibria Measurements, J. Am. Chem. Soc., 1982, 104, 23, 6255, https://doi.org/10.1021/ja00387a016 . [all data]

Cunningham, Payzant, et al., 1972
Cunningham, A.J.; Payzant, J.D.; Kebarle, P., A Kinetic Study of the Proton Hydrate H+(H2O)n Equilibria in the Gas Phase, J. Am. Chem. Soc., 1972, 94, 22, 7627, https://doi.org/10.1021/ja00777a003 . [all data]

Lias, Liebman, et al., 1984
Lias, S.G.; Liebman, J.F.; Levin, R.D., Evaluated gas phase basicities and proton affinities of molecules heats of formation of protonated molecules, J. Phys. Chem. Ref. Data, 1984, 13, 695. [all data]

Keesee and Castleman, 1986
Keesee, R.G.; Castleman, A.W., Jr., Thermochemical data on Ggs-phase ion-molecule association and clustering reactions, J. Phys. Chem. Ref. Data, 1986, 15, 1011. [all data]

Fehsenfeld, Dotan, et al., 1978
Fehsenfeld, F.C.; Dotan, I.; Albritton, D.L.; Howard, C.J.; Ferguson, E.E., Stratospheric Positive Ion Chemistry of Formaldehyde and Methanol, J. Geophys. Res., 1978, 83, C3, 1333, https://doi.org/10.1029/JC083iC03p01333 . [all data]

Meot-Ner (Mautner), 1992
Meot-Ner (Mautner), M., Intermolecular Forces in Organic Clusters, J. Am. Chem. Soc., 1992, 114, 9, 3312, https://doi.org/10.1021/ja00035a024 . [all data]

Larson, Clair, et al., 1982
Larson, J.W.; Clair, R.L.; McMahon, T.B., Bimolecular Production of Proton Bound Dimers in the Gas Phase. A Low Pressure Ion Cyclotron Resonance Technique for Examination of Solvent Exchange Equilibria and Determination of Single Molecule Solvation Energetics, Can. J. Chem., 1982, 60, 4, 542, https://doi.org/10.1139/v82-079 . [all data]

Nee, Osterwalder, et al., 2006
Nee, M.J.; Osterwalder, A.; Zhou, J.; Neumark, D.M., Slow electron velocity-map imaging photoelectron spectra of the methoxide anion, J. Chem. Phys., 2006, 125, 1, 014306, https://doi.org/10.1063/1.2212411 . [all data]

Osborn, Leahy, et al., 1998
Osborn, D.L.; Leahy, D.J.; Kim, E.H.; deBeer, E.; Neumark, D.M., Photoelectron spectroscopy of CH3O- and CD3O-, Chem. Phys. Lett., 1998, 292, 4-6, 651-655, https://doi.org/10.1016/S0009-2614(98)00717-9 . [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]

Rodgers and Armentrout, 2000
Rodgers, M.T.; Armentrout, P.B., Noncovalent Metal-Ligand Bond Energies as Studied by Threshold Collision-Induced Dissociation, Mass Spectrom. Rev., 2000, 19, 4, 215, https://doi.org/10.1002/1098-2787(200007)19:4<215::AID-MAS2>3.0.CO;2-X . [all data]

Woodin and Beauchamp, 1978
Woodin, R.L.; Beauchamp, J.L., Bonding of Li+ to Lewis Bases in the Gas Phase. Reversals in Methyl Substituent Effects for Different Reference Acids, J. Am. Chem. Soc., 1978, 100, 2, 501, https://doi.org/10.1021/ja00470a024 . [all data]

Dzidic and Kebarle, 1970
Dzidic, I.; Kebarle, P., Hydration of the Alkali Ions in the Gas Phase. Enthalpies and Entropies of Reactions M+(H2O)n-1 + H2O = M+(H2O)n, J. Phys. Chem., 1970, 74, 7, 1466, https://doi.org/10.1021/j100702a013 . [all data]

Staley and Beauchamp, 1975
Staley, R.H.; Beauchamp, J.L., Intrinsic Acid - Base Properties of Molecules. Binding Energies of Li+ to pi - and n - Donor Bases, J. Am. Chem. Soc., 1975, 97, 20, 5920, https://doi.org/10.1021/ja00853a050 . [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, Phase change data, Gas phase ion energetics data, Ion clustering data, Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔfH(+) ion,0K	Enthalpy of formation of positive ion at 0K
  ΔfusH	Enthalpy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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