Cyano radical
- Formula: CN
- Molecular weight: 26.0174
- IUPAC Standard InChI: InChI=1S/CN/c1-2
- IUPAC Standard InChIKey: JEVCWSUVFOYBFI-UHFFFAOYSA-N
- CAS Registry Number: 2074-87-5
- Chemical structure:
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Gas phase ion energetics data
Go To: Top, References, Notes
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)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| IE (evaluated) | 13.598 | eV | N/A | N/A | L |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔfH°(+) ion | 1750. ± 4. | kJ/mol | N/A | N/A |
Electron affinity determinations
| EA (eV) | Method | Reference | Comment |
|---|---|---|---|
| 3.8620 ± 0.0050 | LPES | Bradforth, Kim, et al., 1993 | B |
| 3.835 ± 0.091 | D-EA | Bartmess, Scott, et al., 1979 | value altered from reference due to change in acidity scale; B |
| 3.820 ± 0.020 | PD | Berkowitz, Chupka, et al., 1969 | B |
| 5.64 ± 0.20 | R-A | DeCorpo, Bafus, et al., 1971 | From MeCN; B |
| 3.16124 | SI | Chamberlin, Page, et al., 1974 | The Magnetron method, lacking mass analysis, is not considered reliable.; B |
| 2.78398 | SI | Page, 1972 | The Magnetron method, lacking mass analysis, is not considered reliable.; B |
| 2.800 ± 0.020 | SI | Napper and Page, 1963 | New DH(H-CN) used The Magnetron method, lacking mass analysis, is not considered reliable.; B |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 14.17 | EVAL | Huber and Herzberg, 1979 | LLK |
| 14.03 ± 0.02 | DER | Berkowitz, Chupka, et al., 1969 | RDSH |
| ≤14.20 ± 0.02 | DER | Dibeler and Liston, 1967 | RDSH |
| 14.2 ± 0.3 | EI | Berkowitz, 1962 | RDSH |
| 14.5 ± 0.2 | EI | Dibeler, Reese, et al., 1961 | RDSH |
Anion protonation reactions
CN- + =
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 1464. ± 4.2 | kJ/mol | CIDT | Akin and Ervin, 2006 | gas phase; B |
| ΔrH° | 1466.5 ± 0.71 | kJ/mol | D-EA | Bradforth, Kim, et al., 1993 | gas phase; B |
| ΔrH° | 1469. ± 8.8 | kJ/mol | G+TS | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 1433. ± 4.6 | kJ/mol | H-TS | Akin and Ervin, 2006 | gas phase; B |
| ΔrG° | 1435.8 ± 1.1 | kJ/mol | H-TS | Bradforth, Kim, et al., 1993 | gas phase; B |
| ΔrG° | 1438. ± 8.4 | kJ/mol | IMRE | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
References
Go To: Top, 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.
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
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
EA Electron affinity IE (evaluated) Recommended ionization energy 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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