Hydrogen cyanide

• Formula: CHN
• Molecular weight: 27.0253
• IUPAC Standard InChI: InChI=1S/CHN/c1-2/h1H Copy

  
• IUPAC Standard InChIKey: LELOWRISYMNNSU-UHFFFAOYSA-N Copy
• CAS Registry Number: 74-90-8
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: Hydrocyanic acid; AC; Blausaeure (German); Carbon hydride nitride (CHN); Formic anammonide; Formonitrile; HCN; Prussic Acid; Cyclon; Acide cyanhydrique; Acido cianidrico; Aero Liquid HCN; Blausaeure; Blauwzuur; Cyaanwaterstof; Cyanwasserstoff; Cyclone B; Cyjanowodor; Evercyn; NA 1051; Prussic acid, unstabilized; Rcra waste number P063; UN 1051; Zaclondiscoids; Carbon hydride nitride; Zootic acid; Agent AC; Nitrilomethane
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Reaction thermochemistry data (reactions 1 to 50)
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data: reactions 51 to 92
  • Henry's Law data
  • Gas phase ion energetics data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
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Reaction thermochemistry data

Go To: Top, Vibrational and/or electronic energy levels, References, Notes

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.

Reactions 1 to 50

CN^- +  = (CN^- • )

By formula: CN^- + CHN = (CN^- • CHN)

 +  = ( • )

By formula: F^- + CHN = (F^- • CHN)

 +  = ( • )

By formula: Li⁺ + CHN = (Li⁺ • CHN)

 +  = ( • )

By formula: Cl^- + CHN = (Cl^- • CHN)

CN^- +  =

By formula: CN^- + H⁺ = CHN

 +  = ( • )

By formula: CHO₂^- + CHN = (CHO₂^- • CHN)

Free energy of reaction

( • ) +  = ( • 2)

By formula: (CHO₂^- • CHN) + CHN = (CHO₂^- • 2CHN)

Free energy of reaction

( • 3 • ) +  = ( • 4 • )

By formula: (H₄N⁺ • 3CHN • H₃N) + CHN = (H₄N⁺ • 4CHN • H₃N)

Free energy of reaction

( • 8) +  = ( • 9)

By formula: (Cl^- • 8CHN) + CHN = (Cl^- • 9CHN)

Free energy of reaction

( • 4) +  = ( • 5)

By formula: (C₂H₃O₂^- • 4CHN) + CHN = (C₂H₃O₂^- • 5CHN)

Free energy of reaction

(CN^- • 6) +  = (CN^- • 7)

By formula: (CN^- • 6CHN) + CHN = (CN^- • 7CHN)

Free energy of reaction

(CN^- • 2) +  = (CN^- • 3)

By formula: (CN^- • 2CHN) + CHN = (CN^- • 3CHN)

(CN^- • 3) +  = (CN^- • 4)

By formula: (CN^- • 3CHN) + CHN = (CN^- • 4CHN)

(CN^- • ) +  = (CN^- • 2)

By formula: (CN^- • CHN) + CHN = (CN^- • 2CHN)

CH₂N⁺ +  = (CH₂N⁺ • )

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

(CN^- •  • 2) +  = (CN^- • 2 • 2)

By formula: (CN^- • H₂O • 2CHN) + H₂O = (CN^- • 2H₂O • 2CHN)

Free energy of reaction

(CN^- • 3) +  = (CN^- •  • 3)

By formula: (CN^- • 3CHN) + H₂O = (CN^- • H₂O • 3CHN)

Free energy of reaction

(CH₂N⁺ •  • ) +  = (CH₂N⁺ • 2 • )

By formula: (CH₂N⁺ • CHN • H₂O) + CHN = (CH₂N⁺ • 2CHN • H₂O)

( •  • 2) +  = ( • 2 • 2)

By formula: (H₄N⁺ • H₃N • 2CHN) + H₃N = (H₄N⁺ • 2H₃N • 2CHN)

Free energy of reaction

( •  • 2) +  = ( • 2 • 2)

By formula: (H₄N⁺ • CHN • 2H₃N) + CHN = (H₄N⁺ • 2CHN • 2H₃N)

Free energy of reaction

(CN^- • 4) +  = (CN^- • 5)

By formula: (CN^- • 4CHN) + CHN = (CN^- • 5CHN)

( • ) +  = ( •  • )

By formula: (H₄N⁺ • CHN) + H₃N = (H₄N⁺ • H₃N • CHN)

Free energy of reaction

 +  = ( • )

By formula: Br^- + CHN = (Br^- • CHN)

C₄H₉O₂⁺ +  = (C₄H₉O₂⁺ • )

By formula: C₄H₉O₂⁺ + CHN = (C₄H₉O₂⁺ • CHN)

Free energy of reaction

C₃H₇⁺ +  = (C₃H₇⁺ • )

By formula: C₃H₇⁺ + CHN = (C₃H₇⁺ • CHN)

HS^- +  = (HS^- • )

By formula: HS^- + CHN = (HS^- • CHN)

 +  = ( • )

By formula: H₄N⁺ + CHN = (H₄N⁺ • CHN)

(CN^- •  • ) +  = (CN^- • 2 • )

By formula: (CN^- • H₂O • CHN) + H₂O = (CN^- • 2H₂O • CHN)

(CN^- • 2) +  = (CN^- •  • 2)

By formula: (CN^- • 2CHN) + H₂O = (CN^- • H₂O • 2CHN)

(CN^- • ) +  = (CN^- •  • )

By formula: (CN^- • CHN) + H₂O = (CN^- • H₂O • CHN)

( • 7) +  = ( • 8)

By formula: (Cl^- • 7CHN) + CHN = (Cl^- • 8CHN)

(CN^- •  • 2) +  = (CN^- • 2 • 2)

By formula: (CN^- • CHN • 2H₂O) + CHN = (CN^- • 2CHN • 2H₂O)

Free energy of reaction

(CN^- • 2 • ) +  = (CN^- • 3 • )

By formula: (CN^- • 2CHN • H₂O) + CHN = (CN^- • 3CHN • H₂O)

Free energy of reaction

( • 2) +  = ( • 3)

By formula: (Cl^- • 2CHN) + CHN = (Cl^- • 3CHN)

( • 3) +  = ( • 4)

By formula: (Cl^- • 3CHN) + CHN = (Cl^- • 4CHN)

( • ) +  = ( • 2)

By formula: (Cl^- • CHN) + CHN = (Cl^- • 2CHN)

( • 2) +  = ( • 3)

By formula: (I^- • 2CHN) + CHN = (I^- • 3CHN)

( • 2) +  = ( • 3)

By formula: (Br^- • 2CHN) + CHN = (Br^- • 3CHN)

( • 3) +  = ( • 4)

By formula: (Br^- • 3CHN) + CHN = (Br^- • 4CHN)

( • 4) +  = ( • 5)

By formula: (Cl^- • 4CHN) + CHN = (Cl^- • 5CHN)

( • 5) +  = ( • 6)

By formula: (Cl^- • 5CHN) + CHN = (Cl^- • 6CHN)

( • 6) +  = ( • 7)

By formula: (Cl^- • 6CHN) + CHN = (Cl^- • 7CHN)

( • 3) +  = ( • 4)

By formula: (I^- • 3CHN) + CHN = (I^- • 4CHN)

( • 4) +  = ( • 5)

By formula: (I^- • 4CHN) + CHN = (I^- • 5CHN)

( • 5) +  = ( • 6)

By formula: (I^- • 5CHN) + CHN = (I^- • 6CHN)

( • 6) +  = ( • 7)

By formula: (I^- • 6CHN) + CHN = (I^- • 7CHN)

( • 7) +  = ( • 8)

By formula: (I^- • 7CHN) + CHN = (I^- • 8CHN)

( • ) +  = ( • 2)

By formula: (I^- • CHN) + CHN = (I^- • 2CHN)

( • 4) +  = ( • 5)

By formula: (Br^- • 4CHN) + CHN = (Br^- • 5CHN)

( • ) +  = ( • 2)

By formula: (Br^- • CHN) + CHN = (Br^- • 2CHN)

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_∞ν     Symmetry Number σ = 1

Source: Shimanouchi, 1972

Notes

References

Go To: Top, Reaction thermochemistry 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.

Larson and McMahon, 1987
Larson, J.W.; McMahon, T.B., Hydrogen bonding in gas phase anions. The energetics of interaction between cyanide ion and bronsted acids, J. Am. Chem. Soc., 1987, 109, 6230. [all data]

Larson and McMahon, 1984
Larson, J.W.; McMahon, T.B., Gas phase bihalide and pseudohalide ions. An ICR determination of hydrogen bond energies in XHY- species (X,Y = F, Cl, Br, CN), Inorg. Chem., 1984, 23, 2029. [all data]

Meot-Ner (Mautner) and Speller, 1989
Meot-Ner (Mautner), M.; Speller, C.V., Multicomponent Cluster Ions.3. Comparative Stabilities of Cationic and Anionic Hydrogen Bonded Networks. Mixed Clusters of Water and Hydrogen Cyanide, J. Phys. Chem., 1989, 93, 6580. [all data]

Meot-ner, 1988
Meot-ner, M., Ionic Hydrogen Bond and Ion Solvation. ₆. Interaction Energies of the Acetate Ion with Organic Molecules. Comparison of CH₃COO^- with Cl^-, CN^-, and SH^-, J. Am. Chem. Soc., 1988, 110, 12, 3854, https://doi.org/10.1021/ja00220a022 . [all data]

Meot-ner, Cybulski, et al., 1988
Meot-ner, M.; Cybulski, S.M.; Scheiner, S.; Liebman, J.F., Is CN^- Significantly Anisotropic? Comparison of CN^- vs. Cl^-: Clustering with HCN and Condensed Phase Thermochemistry, J. Phys. Chem., 1988, 92, 10, 2738, https://doi.org/10.1021/j100321a009 . [all data]

Payzant, Yamdagni, et al., 1971
Payzant, J.D.; Yamdagni, R.; Kebarle, P., Hydration of CN-, NO₂-, NO₃-, and HO- in the gas phase, Can. J. Chem., 1971, 49, 3308. [all data]

Larson and McMahon, 1983
Larson, J.W.; McMahon, T.B., Strong hydrogen bonding in gas-phase anions. An ion cyclotron resonance determination of fluoride binding energetics to bronsted acids from gas-phase fluoride exchange equilibria measurements, J. Am. Chem. Soc., 1983, 105, 2944. [all data]

Wenthold and Squires, 1995
Wenthold, P.G.; Squires, R.R., Bond dissociation energies of F2(-) and HF2(-). A gas-phase experimental and G2 theoretical study, J. Phys. Chem., 1995, 99, 7, 2002, https://doi.org/10.1021/j100007a034 . [all data]

Arshadi, Yamdagni, et al., 1970
Arshadi, M.; Yamdagni, R.; Kebarle, P., Hydration of Halide Negative Ions in the Gas Phase. II. Comparison of Hydration Energies for the Alkali Positive and Halide Negative Ions, J. Phys. Chem., 1970, 74, 7, 1475, https://doi.org/10.1021/j100702a014 . [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]

Larson and McMahon, 1984, 2
Larson, J.W.; McMahon, T.B., Hydrogen bonding in gas phase anions. An experimental investigation of the interaction between chloride ion and bronsted acids from ICR chloride exchange equilibria, J. Am. Chem. Soc., 1984, 106, 517. [all data]

Larson and McMahon, 1984, 3
Larson, J.W.; McMahon, T.B., Gas phase negative ion chemistry of alkylchloroformates, Can. J. Chem., 1984, 62, 675. [all data]

French, Ikuta, et al., 1982
French, M.A.; Ikuta, S.; Kebarle, P., Hydrogen bonding of O-H and C-H hydrogen donors to Cl^-. Results from mass spectrometric measurement of the ion-molecule equilibria RH + Cl^- = RHCl^-, Can. J. Chem., 1982, 60, 1907. [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]

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]

Deakyne, Knuth, et al., 1994
Deakyne, C.A.; Knuth, D.M.; Speller, C.V.; Meot-Ner (Mautner), M.; Sieck, L.W., Filling of Solvent Shells about Ions. Part 3. Isomeric Clusters of (HCN)n(NH3)mH+, J. Mol. Structure (Theochem), 1994, 307, 217, https://doi.org/10.1016/0166-1280(94)80130-4 . [all data]

Speller and Meot-Ner (Mautner), 1985
Speller, C.V.; Meot-Ner (Mautner), M., The Ionic Hydrogen Bond and Ion Solvation. 3. Bonds Involving Cyanides. Correlations with Proton Affinites, J. Phys. Chem., 1985, 81, 24, 5217, https://doi.org/10.1021/j100270a020 . [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]

Meot-Ner (Mautner) M. and Speller, 1989
Meot-Ner (Mautner) M.; Speller, C.V., Multicomponent Cluster Ions. 2. Comparative Stabilities of Cationic and Anionic Hydrogen Bonded Networks. Mixed Clusters of Water and Hydrogen Cyanide, J. Phys. Chem., 1989, 93, 9, 3663, https://doi.org/10.1021/j100346a058 . [all data]

Meot-Ner (Mautner) and Sieck, 1991
Meot-Ner (Mautner), M.; Sieck, L.W., Proton affinity ladders from variable-temperature equilibrium measurements. 1. A reevaluation of the upper proton affinity range, J. Am. Chem. Soc., 1991, 113, 12, 4448, https://doi.org/10.1021/ja00012a012 . [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, Reaction thermochemistry data, Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  T	Temperature
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

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