Dicarbon monoxide

• Formula: C₂O
• Molecular weight: 40.0208
• IUPAC Standard InChI: InChI=1S/C2O/c1-2-3 Copy

  
• IUPAC Standard InChIKey: VILAVOFMIJHSJA-UHFFFAOYSA-N Copy
• CAS Registry Number: 119754-08-4
• 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.
• Species with the same structure:
  • Dicarbon monoxide
• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
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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.

Gas Phase Heat Capacity (Shomate Equation)

C_p° = 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
    C_p = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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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 by: Edward P. Hunter and Sharon G. Lias

View reactions leading to C₂O⁺ (ion structure unspecified)

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: Marilyn E. Jacox

State:   c

State:   ?

State:   A

State:   b

State:   a

State:   X

Additional references: Jacox, 1994, page 69; Jacox, 1998, page 179; Jacox, 2003, page 111; Pitts, Donnelly, et al., 1981, 2; Yamada, Saito, et al., 1985; Ohshima, Endo, et al., 1995

Notes

References

Go To: Top, Gas phase thermochemistry data, 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.

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

Choi, Mordaunt, et al., 1998
Choi, H.; Mordaunt, D.H.; Bise, R.T.; Taylor, T.R.; Neumark, D.M., Photodissociation of triplet and singlet states of the CCO radical, J. Chem. Phys., 1998, 108, 10, 4070, https://doi.org/10.1063/1.475839 . [all data]

Jacox, Milligan, et al., 1965
Jacox, M.E.; Milligan, D.E.; Moll, N.G.; Thompson, W.E., Matrix-Isolation Infrared Spectrum of the Free Radical CCO, J. Chem. Phys., 1965, 43, 10, 3734, https://doi.org/10.1063/1.1696543 . [all data]

Devillers, 1966
Devillers, C., Compt. Rend. Acad. Sci. (Paris), 1966, 262C, 1485. [all data]

Devillers and Ramsay, 1971
Devillers, C.; Ramsay, D.A., The Band System of the CCO Molecule, Can. J. Phys., 1971, 49, 22, 2839, https://doi.org/10.1139/p71-342 . [all data]

Pitts, Donnelly, et al., 1981
Pitts, W.M.; Donnelly, V.M.; Baronavski, A.P.; McDonald, J.R., C2O(Ã 3Πi↔-~X3Σ-: laser induced excitation and fluorescence spectra, Chem. Phys., 1981, 61, 3, 451, https://doi.org/10.1016/0301-0104(81)85161-0 . [all data]

Fujitake, Kiryu, et al., 1992
Fujitake, M.; Kiryu, R.; Ohashi, N., Near-infrared diode laser spectroscopy of the CCO radical in the band, J. Mol. Spectrosc., 1992, 154, 1, 169, https://doi.org/10.1016/0022-2852(92)90037-O . [all data]

Ohashi, Kiryu, et al., 1993
Ohashi, N.; Kiryu, R.; Okino, S.; Fujitake, M., Near-Infrared Diode Laser Spectroscopy of the CCO Radical: Molecular Constants for the X3Σ-(010) State, J. Mol. Spectrosc., 1993, 157, 1, 50, https://doi.org/10.1006/jmsp.1993.1004 . [all data]

Abe, Kikuchi, et al., 1994
Abe, H.; Kikuchi, T.; Takahashi, K.; Fujitake, M.; Ohashi, N., Near-Infrared Diode Laser Spectroscopy of the CCO Radical: Analysis of the Ã(010)3Σ(+) and Ã(010)3Σ(-) States, J. Mol. Spectrosc., 1994, 167, 2, 353, https://doi.org/10.1006/jmsp.1994.1241 . [all data]

Abe, Kawamoto, et al., 1996
Abe, H.; Kawamoto, Y.; Fujitake, M.; Ohashi, N.; Momose, T.; Shida, T., Laser Spectroscopy of the CCO Radical in the 0.77-μm Region: Analysis of theÃ(020)κ3Π andÃ3Πi(001) States, J. Mol. Spectrosc., 1996, 180, 2, 277, https://doi.org/10.1006/jmsp.1996.0250 . [all data]

Abe, Mukai, et al., 1999
Abe, H.; Mukai, M.; Fujitaki, M.; Ohashi, N., Near-Infrared Diode--Laser Spectroscopy of the CCO Radical in theÃ(010)3Δ--X(010)3Π(b) Band, J. Mol. Spectrosc., 1999, 195, 2, 317, https://doi.org/10.1006/jmsp.1999.7835 . [all data]

Garand, Yacovitch, et al., 2008
Garand, E.; Yacovitch, T.I.; Neumark, D.M., Slow photoelectron imaging spectroscopy of CCO- and CCS-, J. Chem. Phys., 2008, 129, 7, 074312, https://doi.org/10.1063/1.2969819 . [all data]

Fulara, Grutter, et al., 1998
Fulara, J.; Grutter, M.; Wyss, M.; Maier, J.P., A, J. Phys. Chem. A, 1998, 102, 20, 3459, https://doi.org/10.1021/jp980879t . [all data]

Smith and Weltner, 1975
Smith, G.R.; Weltner, W., Jr., ESR of the triplet molecules CCO and CNN in rare-gas matrices; isotope and matrix effects, J. Chem. Phys., 1975, 62, 12, 4592, https://doi.org/10.1063/1.430432 . [all data]

Ohashi and Fujitake, 2004
Ohashi, N.; Fujitake, M., Spectrochim. Acta, 2004, 60A, 3277. [all data]

Zengin, Persson, et al., 1996
Zengin, V.; Persson, B.J.; Strong, K.M.; Continetti, R.E., Study of the Low-lying Electronic States of CCO by Photoelectron Spectroscopy of CCO- and ab initio calculations., J. Chem. Phys., 1996, 105, 22, 9740, https://doi.org/10.1063/1.473000 . [all data]

Moazzen-Ahmadi and Boere, 1999
Moazzen-Ahmadi, N.; Boere, R.T., Infrared laser spectroscopy of CCO: The ν[sub 1] band of the a[sup 1]Δ electronic state, J. Chem. Phys., 1999, 110, 2, 955, https://doi.org/10.1063/1.478140 . [all data]

Abusara, Sorensen, et al., 2004
Abusara, Z.; Sorensen, T.S.; Moazzen-Ahmadi, N., Infrared laser spectroscopy of CCO: the ν3 band of the electronic state and 3ν3--2ν3 band of the ground electronic state, Chem. Phys. Lett., 2004, 388, 1-3, 62, https://doi.org/10.1016/j.cplett.2004.03.010 . [all data]

Yamada, Kanamori, et al., 1986
Yamada, C.; Kanamori, H.; Horiguchi, H.; Tsuchiya, S.; Hirota, E., Infrared diode laser kinetic spectroscopy of the CCO radical in the X 3Σ- state generated by the excimer laser photolysis of carbon suboxide, J. Chem. Phys., 1986, 84, 5, 2573, https://doi.org/10.1063/1.450835 . [all data]

Moazzen-Ahmadi, Sandilands, et al., 1997
Moazzen-Ahmadi, N.; Sandilands, D.W.D.; Boere, R.T., Infrared diode laser spectroscopy of the ν1 fundamental and the ν1 + ν2 - ν2 sequence bands of the CCO radical, Chem. Phys. Lett., 1997, 265, 6, 563, https://doi.org/10.1016/S0009-2614(96)01451-0 . [all data]

DeKock and Weltner, 1971
DeKock, R.L.; Weltner, W., Jr., C2O, CN2, and C3O molecules, J. Am. Chem. Soc., 1971, 93, 25, 7106, https://doi.org/10.1021/ja00754a081 . [all data]

Abusara, Sorensen, et al., 2003
Abusara, Z.; Sorensen, T.S.; Moazzen-Ahmadi, N., Infrared laser spectroscopy of CCO radical in the region of the C--C stretching fundamental, J. Chem. Phys., 2003, 119, 18, 9491, https://doi.org/10.1063/1.1615752 . [all data]

Jacox, 1994
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules, American Chemical Society, Washington, DC, 1994, 464. [all data]

Jacox, 1998
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement A, J. Phys. Chem. Ref. Data, 1998, 27, 2, 115-393, https://doi.org/10.1063/1.556017 . [all data]

Jacox, 2003
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement B, J. Phys. Chem. Ref. Data, 2003, 32, 1, 1-441, https://doi.org/10.1063/1.1497629 . [all data]

Pitts, Donnelly, et al., 1981, 2
Pitts, W.M.; Donnelly, V.M.; Baronavski, A.P.; McDonald, J.R., Excited state dynamics of C2O( 3Πi), Chem. Phys., 1981, 61, 3, 465, https://doi.org/10.1016/0301-0104(81)85162-2 . [all data]

Yamada, Saito, et al., 1985
Yamada, C.; Saito, S.; Kanamori, H.; Hirota, E., Millimeter-wave spectrum of the CCO radical, Astrophys. J., 1985, 290, L65, https://doi.org/10.1086/184444 . [all data]

Ohshima, Endo, et al., 1995
Ohshima, Y.; Endo, Y.; Ogata, T., Fourier-transform microwave spectroscopy of triplet carbon monoxides, C2O, C4O, C6O, and C8O, J. Chem. Phys., 1995, 102, 4, 1493, https://doi.org/10.1063/1.468881 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

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