Cyano radical

• Formula: CN
• Molecular weight: 26.0174
• IUPAC Standard InChI: InChI=1S/CN/c1-2 Copy

  
• IUPAC Standard InChIKey: JEVCWSUVFOYBFI-UHFFFAOYSA-N Copy
• CAS Registry Number: 2074-87-5
• 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.
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• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Constants of diatomic molecules
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
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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 (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/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 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
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 CN⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

Anion protonation reactions

CN^- +  =

By formula: CN^- + H⁺ = CHN

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]

Bradforth, Kim, et al., 1993
Bradforth, S.E.; Kim, E.H.; Arnold, D.W.; Neumark, D.M., Photoelectron Spectroscopy of CN-, NCO-, and NCS-, J. Chem. Phys., 1993, 98, 2, 800, https://doi.org/10.1063/1.464244 . [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]

Berkowitz, Chupka, et al., 1969
Berkowitz, J.; Chupka, W.A.; Walter, T.A., Photoionization of HCN: the electron affinity and heat of formation of CN, J. Chem. Phys., 1969, 50, 1497. [all data]

DeCorpo, Bafus, et al., 1971
DeCorpo, J.J.; Bafus, D.A.; Franklin, J.L., Correlation of excess energies of dissociative electron attachment processes with the translational energies of their products, J. Chem. Phys., 1971, 54, 1592. [all data]

Chamberlin, Page, et al., 1974
Chamberlin, A.T.; Page, F.M.; Painter, M.R., A Study of the Negative Ions Produced during Surface Ionization on Hot Metal Filaments, Adv. Mass Spectrom., 1974, 6, 311. [all data]

Page, 1972
Page, F.M., Experimental determination of the electron affinities of inorganic radicals, Adv. Chem. Ser., 1972, 36, 68. [all data]

Napper and Page, 1963
Napper, R.; Page, F.M., Determination of Electron Affinities. Part 5. Cyanide and Thiocyanate Radicals, Trans. Farad. Soc., 1963, 59, 1086, https://doi.org/10.1039/tf9635901086 . [all data]

Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979, ,1. [all data]

Dibeler and Liston, 1967
Dibeler, V.H.; Liston, S.K., Mass-spectrometric study of photoionization. VIII.Dicyanogen and the cyanogen halides, J. Chem. Phys., 1967, 47, 4548. [all data]

Berkowitz, 1962
Berkowitz, J., Heat of formation of the CN radical, J. Chem. Phys., 1962, 36, 2533. [all data]

Dibeler, Reese, et al., 1961
Dibeler, V.H.; Reese, R.M.; Franklin, J.L., Mass spectrometric study of cyanogen and cyanoacetylenes, J. Am. Chem. Soc., 1961, 83, 1813. [all data]

Akin and Ervin, 2006
Akin, F.A.; Ervin, K.M., Collision-induced dissociation of HS-(HCN): Unsymmetrical hydrogen bonding in a proton-bound dimer anion, J. Phys. Chem. A, 2006, 110, 4, 1342-1349, https://doi.org/10.1021/jp0540454 . [all data]

Notes

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• Symbols used in this document:
  

  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  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

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