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CH2=C=CH anion


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 by: John E. Bartmess

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Individual Reactions

C3H3- + Hydrogen cation = Allene

By formula: C3H3- + H+ = C3H4

Quantity Value Units Method Reference Comment
Deltar1590. ± 8.4kJ/molD-EARobinson, Polak, et al., 1995gas phase; Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic.
Deltar1596. ± 13.kJ/molG+TSRobinson, Polak, et al., 1995gas phase; Relative to MeOH at 375.0; kinetic scheme factors in isomerization
Deltar1592. ± 8.8kJ/molD-EAOakes and Ellison, 1983gas phase; Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic.
Quantity Value Units Method Reference Comment
Deltar1560. ± 13.kJ/molIMRERobinson, Polak, et al., 1995gas phase; Relative to MeOH at 375.0; kinetic scheme factors in isomerization
Deltar1556. ± 9.2kJ/molH-TSOakes and Ellison, 1983gas phase; Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic.

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 compiled by: John E. Bartmess

Electron affinity of neutral species

EAneutral (eV) Method Reference Comment
0.9180 ± 0.0080LPESRobinson, Polak, et al., 1995Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic.
0.893 ± 0.026LPESOakes and Ellison, 1983Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic.
2.34166SIPage and Goode, 1969The Magnetron method, lacking mass analysis, is not considered reliable.

Protonation reactions

C3H3- + Hydrogen cation = Allene

By formula: C3H3- + H+ = C3H4

Quantity Value Units Method Reference Comment
Deltar1590. ± 8.4kJ/molD-EARobinson, Polak, et al., 1995gas phase; Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic.
Deltar1596. ± 13.kJ/molG+TSRobinson, Polak, et al., 1995gas phase; Relative to MeOH at 375.0; kinetic scheme factors in isomerization
Deltar1592. ± 8.8kJ/molD-EAOakes and Ellison, 1983gas phase; Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic.
Quantity Value Units Method Reference Comment
Deltar1560. ± 13.kJ/molIMRERobinson, Polak, et al., 1995gas phase; Relative to MeOH at 375.0; kinetic scheme factors in isomerization
Deltar1556. ± 9.2kJ/molH-TSOakes and Ellison, 1983gas phase; Neutral acid: allene. Propyne would be 1.0 kcal/mol less acidic.

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: Marilyn E. Jacox

State:   A


 Energy 
 (cm-1
 Med.   Transition   «lambda»min 
 (nm) 
 «lambda»max 
 (nm) 
 References

Td = 7410 gas Oakes and Ellison, 1983
Robinson, Polak, et al., 1995

State:   X


Vib. 
sym. 
 No.   Approximate 
 type of mode 
 cm-1   Med.   Method   References

C3 a-stretch 1857.9 Ne IR Forney, Jacox, et al., 2001
687.0 Ne IR Forney, Jacox, et al., 2001

Additional references: Jacox, 1998, page 311; Jacox, 2003, page 316

Notes

dPhotodissociation threshold

References

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics 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.

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]

Forney, Jacox, et al., 2001
Forney, D.; Jacox, M.E.; Lugez, C.L.; Thompson, W.E., Matrix isolation study of the interaction of excited neon atoms with allene and propyne: Infrared spectra of H[sub 2]CCCH[sub 2][sup +] and H[sub 2]CCCH[sup -], J. Chem. Phys., 2001, 115, 18, 8418, https://doi.org/10.1063/1.1402998 . [all data]

Jacox, 1998
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement A, J. Phys. Chem. Ref. Data, 1998, 27, 2, 115-393, https://doi.org/10.1063/1.556017 . [all data]

Jacox, 2003
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement B, J. Phys. Chem. Ref. Data, 2003, 32, 1, 1-441, https://doi.org/10.1063/1.1497629 . [all data]


Notes

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