CH2=C=CH anion
- Formula: C3H3-
- Molecular weight: 39.0565
- CAS Registry Number: 64066-06-4
- Information on this page:
- Other data available:
- Options:
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 compiled by: John E. Bartmess
Electron affinity of neutral species
| EAneutral (eV) | Method | Reference | Comment |
|---|---|---|---|
| 0.9180 ± 0.0080 | LPES | Robinson, Polak, et al., 1995 | Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic. |
| 0.893 ± 0.026 | LPES | Oakes and Ellison, 1983 | Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic. |
| 2.34166 | SI | Page and Goode, 1969 | The Magnetron method, lacking mass analysis, is not considered reliable. |
Protonation reactions
C3H3- + =
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 1590. ± 8.4 | kJ/mol | D-EA | Robinson, Polak, et al., 1995 | gas phase; Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic. |
| ΔrH° | 1596. ± 13. | kJ/mol | G+TS | Robinson, Polak, et al., 1995 | gas phase; Relative to MeOH at 375.0; kinetic scheme factors in isomerization |
| ΔrH° | 1592. ± 8.8 | kJ/mol | D-EA | Oakes and Ellison, 1983 | gas phase; Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic. |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 1560. ± 13. | kJ/mol | IMRE | Robinson, Polak, et al., 1995 | gas phase; Relative to MeOH at 375.0; kinetic scheme factors in isomerization |
| ΔrG° | 1556. ± 9.2 | kJ/mol | H-TS | Oakes and Ellison, 1983 | gas phase; Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic. |
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.
Robinson, Polak, et al., 1995
Robinson, M.S.; Polak, M.L.; Bierbaum, V.M.; DePuy, C.H.; Lineberger, W.C.,
Experimental Studies of Allene, Methylacetylene, and the Propargyl Radical: Bond Dissociation Energies, Gas-Phase Acidities, and Ion-Molecule Chemistry,
J. Am. Chem. Soc., 1995, 117, 25, 6766, https://doi.org/10.1021/ja00130a017
. [all data]
Oakes and Ellison, 1983
Oakes, J.M.; Ellison, B.G.,
Photoelectron spectroscopy of the allenyl anion CH2=C=CH-,
J. Am. Chem. Soc., 1983, 105, 2969. [all data]
Page and Goode, 1969
Page, F.M.; Goode, G.C.,
Negative Ions and the Magnetron., Wiley, NY, 1969. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
EAneutral Electron affinity of neutral species 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
- The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
- Customer support for NIST Standard Reference Data products.