Cyanogen
- Formula: C2N2
- Molecular weight: 52.0348
- IUPAC Standard InChI: InChI=1S/C2N2/c3-1-2-4
- IUPAC Standard InChIKey: JMANVNJQNLATNU-UHFFFAOYSA-N
- CAS Registry Number: 460-19-5
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
View 3d structure (requires JavaScript / HTML 5) - Other names: Ethanedinitrile; Cyanogen (C2N2); Carbon nitride (C2N2); Dicyanogen; Nitriloacetonitrile; Oxalic acid dinitrile; Oxalonitrile; NCCN; Dicyan; Cyanogen gas; Carbon nitride; Cyanogene; Oxalic nitrile; Prussite; Rcra waste number P031; UN 1026; (CN)2; Oxalyl cyanide
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Condensed 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.
Data compiled by: Eugene S. Domalski and Elizabeth D. Hearing
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| S°liquid | 138.83 | J/mol*K | N/A | Ruehrwein and Giauque, 1939 |
Constant pressure heat capacity of liquid
| Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 105.73 | 255. | Ruehrwein and Giauque, 1939 | T = 15 to 252 K. |
Phase change 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
DH - Eugene S. Domalski and Elizabeth D. Hearing
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| Tboil | 252.0 | K | N/A | Weast and Grasselli, 1989 | BS |
| Tboil | 252. | K | N/A | Majer and Svoboda, 1985 | |
| Quantity | Value | Units | Method | Reference | Comment |
| Ttriple | 245.32 | K | N/A | Ruehrwein and Giauque, 1939, 2 | Uncertainty assigned by TRC = 0.02 K; TRC |
| Quantity | Value | Units | Method | Reference | Comment |
| Ptriple | 0.751 | bar | N/A | Hamann, Mcmanamey, et al., 1953 | Uncertainty assigned by TRC = 0.0133 bar; TRC |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔvapH° | 20.8 | kJ/mol | N/A | Majer and Svoboda, 1985 |
Enthalpy of vaporization
| ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 23.330 | 252.0 | N/A | Ruehrwein and Giauque, 1939 | P = 101.325 kPa; DH |
| 23.33 | 252. | N/A | Majer and Svoboda, 1985 | |
| 24.5 | 246. | A | Stephenson and Malanowski, 1987 | Based on data from 240. to 253. K.; AC |
| 23.3 ± 0.2 | 251.95 | V | Ruehrwein and Giauque, 1939, 3 | ALS |
| 23.9 | 257. | N/A | Perry and Bardwell, 1925 | Based on data from 246. to 273. K.; AC |
| 23.5 | 267. | N/A | Perry and Bardwell, 1925 | Based on data from 246. to 273. K.; AC |
Entropy of vaporization
| ΔvapS (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 92.58 | 252.0 | Ruehrwein and Giauque, 1939 | P; DH |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (bar)
T = temperature (K)
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| Temperature (K) | A | B | C | Reference | Comment |
|---|---|---|---|---|---|
| 252. to 391.3 | 4.51661 | 1041.518 | -21.288 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
Enthalpy of sublimation
| ΔsubH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 33.0 | 224. | N/A | Stephenson and Malanowski, 1987 | Based on data from 202. to 239. K.; AC |
| 32.4 | 224. | N/A | Govers, 1975 | Based on data from 198. to 240. K. See also Perry and Bardwell, 1925.; AC |
| 33.6 | 204. | A | Stull, 1947 | Based on data from 177. to 230. K.; AC |
| 34.4 | 202. to 245. | CATH | Ruehrwein and Giauque, 1939 | AC |
Enthalpy of fusion
| ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 8.109 | 245.32 | Ruehrwein and Giauque, 1939 | DH |
| 8.11 | 245.3 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
| ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 33.05 | 245.32 | Ruehrwein and Giauque, 1939 | DH |
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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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
+
= (
•
)
By formula: H4N+ + C2N2 = (H4N+ • C2N2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 43.5 | kJ/mol | PHPMS | Speller and Meot-Ner (Mautner), 1985 | gas phase; Entropy change calculated or estimated, DG<, ΔrH<; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 96. | J/mol*K | N/A | Speller and Meot-Ner (Mautner), 1985 | gas phase; Entropy change calculated or estimated, DG<, ΔrH<; M |
Free energy of reaction
| ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 13. | 315. | PHPMS | Speller and Meot-Ner (Mautner), 1985 | gas phase; Entropy change calculated or estimated, DG<, ΔrH<; M |
+
= 2
By formula: C2N2 + C2F6 = 2C2F3N
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 44.10 ± 0.59 | kJ/mol | Eqk | Walker, Sinke, et al., 1970 | gas phase; ALS |
Ion clustering 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 by: 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. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
+
= (
•
)
By formula: H4N+ + C2N2 = (H4N+ • C2N2)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 43.5 | kJ/mol | PHPMS | Speller and Meot-Ner (Mautner), 1985 | gas phase; Entropy change calculated or estimated, DG<, ΔrH< |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 96. | J/mol*K | N/A | Speller and Meot-Ner (Mautner), 1985 | gas phase; Entropy change calculated or estimated, DG<, ΔrH< |
Free energy of reaction
| ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 13. | 315. | PHPMS | Speller and Meot-Ner (Mautner), 1985 | gas phase; Entropy change calculated or estimated, DG<, ΔrH< |
IR Spectrum
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Data compiled by: Coblentz Society, Inc.
- GAS; Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm-1 resolution
- GAS (280 mmHg DILUTED TO A TOTAL PRESSURE OF 600 mmHg WITH N2); DOW KBr FOREPRISM-GRATING; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm-1 resolution
- GAS (280 mmHg, N2 ADDED, TOTAL PRESSURE 600 mmHg); DOW KBr FOREPRISM-GRATING; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 2 cm-1 resolution
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: Dxh Symmetry Number σ = 2
| Sym. | No | Approximate | Selected Freq. | Infrared | Raman | Comments | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Species | type of mode | Value | Rating | Value | Phase | Value | Phase | |||
| σg+ | 1 | CN s-str | 2330 | B | 2339.9 | gas | 2330.5 | gas | Determined from difference bands | |
| σg+ | 2 | NN str | 846 | C | ia | 845.5 | gas | |||
| σu+ | 3 | CN a-str | 2158 | A | 2157.83 | gas | ia | |||
| πg | 4 | CCN bend | 503 | C | ia | 502.8 | gas | |||
| πu | 5 | CCN bend | 234 | B | 233.1 | gas | 233.7 | gas | Determined from difference bands | |
Source: Shimanouchi, 1972
Notes
| ia | Inactive |
| A | 0~1 cm-1 uncertainty |
| B | 1~3 cm-1 uncertainty |
| C | 3~6 cm-1 uncertainty |
Gas Chromatography
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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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Kovats' RI, non-polar column, isothermal
| Column type | Active phase | Temperature (C) | I | Reference | Comment |
|---|---|---|---|---|---|
| Capillary | CP Sil 5 CB | 20. | 259.2 | Do and Raulin, 1992 | 25. m/0.15 mm/2. μm, H2 |
| Capillary | PoraPLOT Q | 160. | 273. | Do and Raulin, 1989 | 10. m/0.32 mm/10. μm, H2 |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Ion clustering data, IR Spectrum, Vibrational and/or electronic energy levels, Gas Chromatography, NIST Free Links, NIST Subscription Links, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Ruehrwein and Giauque, 1939
Ruehrwein, R.A.; Giauque, W.F.,
The entropy of cyanogen. Heat capacity and vapor pressure of solid and liquid. Heats of fusion and vaporization,
J. Am. Chem. Soc., 1939, 61, 2940-2944. [all data]
Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]
Majer and Svoboda, 1985
Majer, V.; Svoboda, V.,
Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]
Ruehrwein and Giauque, 1939, 2
Ruehrwein, R.A.; Giauque, W.F.,
The entropy of cyanogen heat capacity and vapor pressure of solid and liquid heats of fusion and vaporization,
J. Am. Chem. Soc., 1939, 61, 2940-4. [all data]
Hamann, Mcmanamey, et al., 1953
Hamann, S.D.; Mcmanamey, W.J.; Pearse, J.F.,
The forces between polyatomic molecules,
Trans. Faraday Soc., 1953, 49, 351. [all data]
Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw,
Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2
. [all data]
Ruehrwein and Giauque, 1939, 3
Ruehrwein, R.A.; Giauque, W.F.,
The entropy of cyanogen. Heat capacity and vapor pressure of solid and liquid. Heats of fusion and vaporization,
J. Am. Chem. Soc., 1939, 61, 2940-29. [all data]
Perry and Bardwell, 1925
Perry, John H.; Bardwell, D.C.,
THE VAPOR PRESSURES OF SOLID AND LIQUID CYANOGEN 1,
J. Am. Chem. Soc., 1925, 47, 11, 2629-2632, https://doi.org/10.1021/ja01688a002
. [all data]
Stull, 1947
Stull, Daniel R.,
Vapor Pressure of Pure Substances. Organic and Inorganic Compounds,
Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022
. [all data]
Govers, 1975
Govers, H.A.J.,
Derivation of carbon--nitrogen, hydrogen--nitrogen and nitrogen--nitrogen non-bonded potential parameters in molecular crystals,
Acta Crystallogr Sect A Cryst Phys Diffr Theor Gen Crystallogr', 1975, 31, 3, 380-385, https://doi.org/10.1107/S0567739475000800
. [all data]
Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D.,
Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III,
J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985
. [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]
Walker, Sinke, et al., 1970
Walker, L.C.; Sinke, G.C.; Perettie, D.J.; Janz, G.J.,
Enthalpy of formation of trifluoroacetonitrile,
J. Am. Chem. Soc., 1970, 92, 4525-4526. [all data]
Shimanouchi, 1972
Shimanouchi, T.,
Tables of Molecular Vibrational Frequencies Consolidated Volume II,
J. Phys. Chem. Ref. Data, 1972, 6, 3, 993-1102. [all data]
Do and Raulin, 1992
Do, L.; Raulin, F.,
Gas chromatography of Titan's atmosphere. III. Analysis of low-molecular-weight hydrocarbons and nitriles with a CP-Sil-5 CB WCOT capillary column,
J. Chromatogr., 1992, 591, 1-2, 297-301, https://doi.org/10.1016/0021-9673(92)80247-R
. [all data]
Do and Raulin, 1989
Do, L.; Raulin, F.,
Gas chromatography of Titan's atmosphere. I. Analysis of low-molecular-weight hydrocarbons and nitriles with a PoraPLOT Q porous polymer coated open-tubular capillary column,
J. Chromatogr., 1989, 481, 45-54, https://doi.org/10.1016/S0021-9673(01)96751-2
. [all data]
Notes
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- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid Ptriple Triple point pressure S°liquid Entropy of liquid at standard conditions T Temperature Tboil Boiling point Ttriple Triple point temperature ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions ΔsubH Enthalpy of sublimation ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions ΔvapS Entropy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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