Dicarbon

• Formula: C₂
• Molecular weight: 24.0214
• IUPAC Standard InChI: InChI=1S/C2/c1-2 Copy

  
• IUPAC Standard InChIKey: LBVWYGNGGJURHQ-UHFFFAOYSA-N Copy
• CAS Registry Number: 12070-15-4
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
  • Ion clustering data
  • Constants of diatomic molecules
• Data at other public NIST sites:
  • Computational Chemistry Comparison and Benchmark Database
  • Gas Phase Kinetics Database
• Options:
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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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Reaction 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

(C₂H^- • 4294967295) +  = C₂H^-

By formula: (C₂H^- • 4294967295C₂) + C₂ = C₂H^-

( • 2) +  = ( •  • 2)

By formula: (C⁺ • 2C) + C₂ = (C⁺ • C₂ • 2C)

C₆₂⁺ +  = (C₆₂⁺ • )

By formula: C₆₂⁺ + C₂ = (C₆₂⁺ • C₂)

C₅₈⁺ +  = (C₅₈⁺ • )

By formula: C₅₈⁺ + C₂ = (C₅₈⁺ • C₂)

C₆₀⁺ +  = (C₆₀⁺ • )

By formula: C₆₀⁺ + C₂ = (C₆₀⁺ • C₂)

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry 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]

Zhou, Garand, et al., 2007
Zhou, J.; Garand, E.; Neumark, D.M., Vibronic structure in C2H and C2D from anion slow electron velocity-map imaging spectroscopy, J. Chem. Phys., 2007, 127, 11, 114313, https://doi.org/10.1063/1.2768932 . [all data]

Ruscic and Berkowitz, 1990
Ruscic, B.; Berkowitz, J., Photoion-pair Formation and Photoelectron-induced Dissociative Attachment in C2H2: D0(HCC-H), J. Chem. Phys., 1990, 93, 8, 5586, https://doi.org/10.1063/1.459629 . [all data]

Gurvich, Veyts, et al.
Gurvich, L.V.; Veyts, I.V.; Alcock, C.B., Hemisphere Publishing, NY, 1989, V. 1 2, Thermodynamic Properties of Individual Substances, 4th Ed. [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]

Radi, Rincon, et al., 1989
Radi, P.P.; Rincon, M.E.; Hsu, M.T.; Brodbelt-Lustig, J.; Kemper, P.; Bowers, M.T., Structure, Reactivity and Energetics of Covalently Bound Carbon Cluster Ions, C5+ to C11+: Experiment and Theory, J. Phys. Chem., 1989, 93, 16, 6187, https://doi.org/10.1021/j100353a045 . [all data]

Radi, Hsu, et al., 1990
Radi, P.R.; Hsu, M.T.; Rincon, M.E.; Kemper, P.R.; Bowers, M.T., On the Structure, Reactivity and Relative Stability of the Large Carbon Cluster Ions C62+, C60+ and C58+, Chem. Phys. Lett., 1990, 174, 3-4, 223, https://doi.org/10.1016/0009-2614(90)85336-B . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, 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
  ΔrH°	Enthalpy of reaction at standard conditions

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