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Carbon anion


Gas 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 as indicated in comments:
B - John E. Bartmess

Quantity Value Units Method Reference Comment
Deltafgas499. ± 16.kJ/molR-EAErvin, Gronert, et al., 1990B
Deltafgas<826. ± 19.kJ/molEIAECollin and Locht, 1970From ketene; B
Quantity Value Units Method Reference Comment
gas,1 bar196.60J/mol*KReviewChase, 1998Data last reviewed in December, 1969

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

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

Carbon anion + Hydrogen cation = C2H

By formula: C2- + H+ = C2H

Quantity Value Units Method Reference Comment
Deltar>1460. ± 15.kJ/molD-EAArnold, Bradforth, et al., 1991gas phase
Deltar<1572. ± 9.6kJ/molG+TSSchiff and Bohme, 1975gas phase; No reaction with acetylene
Quantity Value Units Method Reference Comment
Deltar>1430. ± 16.kJ/molH-TSArnold, Bradforth, et al., 1991gas phase
Deltar<1542. ± 8.4kJ/molIMRBSchiff and Bohme, 1975gas phase; No reaction with acetylene

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Constants of diatomic molecules, 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

Protonation reactions

Carbon anion + Hydrogen cation = C2H

By formula: C2- + H+ = C2H

Quantity Value Units Method Reference Comment
Deltar>1460. ± 15.kJ/molD-EAArnold, Bradforth, et al., 1991gas phase
Deltar<1572. ± 9.6kJ/molG+TSSchiff and Bohme, 1975gas phase; No reaction with acetylene
Quantity Value Units Method Reference Comment
Deltar>1430. ± 16.kJ/molH-TSArnold, Bradforth, et al., 1991gas phase
Deltar<1542. ± 8.4kJ/molIMRBSchiff and Bohme, 1975gas phase; No reaction with acetylene

Constants of diatomic molecules

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, 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: Klaus P. Huber and Gerhard H. Herzberg

Data collected through July, 1976

Symbols used in the table of constants
SymbolMeaning
State electronic state and / or symmetry symbol
Te minimum electronic energy (cm-1)
ωe vibrational constant – first term (cm-1)
ωexe vibrational constant – second term (cm-1)
ωeye vibrational constant – third term (cm-1)
Be rotational constant in equilibrium position (cm-1)
αe rotational constant – first term (cm-1)
γe rotation-vibration interaction constant (cm-1)
De centrifugal distortion constant (cm-1)
βe rotational constant – first term, centrifugal force (cm-1)
re internuclear distance (Å)
Trans. observed transition(s) corresponding to electronic state
ν00 position of 0-0 band (units noted in table)
Diatomic constants for 12C2-
StateTeomegaeomegaexeomegaeyeBealphaegammaeDebetaereTrans.nu00
a 4Sigmau+ (19448) (1074) 1 (25)  (1.135) 1 (0.0035)    (1.573)  
B 2Sigmau+ 18390.88 1968.73 Z 14.433 -0.324 1.87745 2 0.01776 -0.00037 0.00000684 3  1.22330 B lrarrow X 4 V 18483.98 Z
missing citation
A 2Piu 5           A larrow X 
Lineberger and Patterson, 1972
X 2Sigmag+ 0 1781.04 Z 11.585 -0.027 1.74685 0.0167  0.00000669  1.26821  

Notes

1Constants derived Bondybey and Brus, 1975 from the perturbations Herzberg and Lagerqvist, 1968 in B 2Sigmau+. Ab initio calculations by Barsuhn, 1974 and Thulstrup and Thulstrup, 1974 independently predict the existence of a 4Sigmau+ state slightly above B 2Sigmau+ with re and omegae values near those derived from the perturbations.
2Small perturbations by a 4Sigmau+.
3Dv= +[1.0(v+1/2) + 0.08(v+1.2)2]E-7.
4The spectrum was observed in flash discharges in CH4 Herzberg and Lagerqvist, 1968, behind reflected shock waves [fel ~ 0.017 Cathro and Mackie, 1973], and in rare gas matrices Milligan and Jacox, 1969, Frosch, 1971, Bondybey and Nibler, 1972, missing citation, Brus and Bondybey, 1975. Conclusive proof that it belongs to C2- was supplied by two-photon photodetachment spectroscopy Lineberger and Patterson, 1972. Franck-Condon factors Singh and Maheshwari, 1971.
5Fragments of absorption bands.
6From D00(C2) and the electron affinities of C2 and of C(=1.268 eV).
7Photodetachment threshold Feldman, 1970.

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Ervin, Gronert, et al., 1990
Ervin, K.M.; Gronert, S.; Barlow, S.E.; Gilles, M.K.; Harrison, A.G.; Bierbaum, V.M.; DePuy, C.H.; Lin, W.C., Bonds Strengths of Ethylene and Acetylene, J. Am. Chem. Soc., 1990, 112, 15, 5750, https://doi.org/10.1021/ja00171a013 . [all data]

Collin and Locht, 1970
Collin, J.E.; Locht, R., Positive and negative ion formation in ketene by electron impact, Intern. J. Mass Spectrom. Ion Phys., 1970, 3, 465. [all data]

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Arnold, Bradforth, et al., 1991
Arnold, D.W.; Bradforth, S.E.; Kitsopoulos, T.N.; Neumark, D.M., Vibrationally Resolved Spectra of C2-C11 by Anion Photoelectron Spectroscopy, J. Chem. Phys., 1991, 95, 12, 8753, https://doi.org/10.1063/1.461211 . [all data]

Schiff and Bohme, 1975
Schiff, H.I.; Bohme, D.K., Flowing afterglow studies at York University, Int. J. Mass Spectrom. Ion Phys., 1975, 16, 167. [all data]

Lineberger and Patterson, 1972
Lineberger, W.C.; Patterson, T.A., Two photon photodetachment spectroscopy: the C2--2«SIGMA» states, Chem. Phys. Lett., 1972, 13, 40. [all data]

Bondybey and Brus, 1975
Bondybey, V.E.; Brus, L.E., Photophysics of C2-(B2«SIGMA»u+) in rare gas lattices: vibrational relaxation through intermediate a4«SIGMA»u+ levels, J. Chem. Phys., 1975, 63, 2223. [all data]

Herzberg and Lagerqvist, 1968
Herzberg, G.; Lagerqvist, A., A new spectrum associated with diatomic carbon, Can. J. Phys., 1968, 46, 2363. [all data]

Barsuhn, 1974
Barsuhn, J., Nonempirical calculations on the electronic spectrum of the molecular ion C2-, J. Phys. B:, 1974, 7, 155. [all data]

Thulstrup and Thulstrup, 1974
Thulstrup, P.W.; Thulstrup, E.W., A theoretical investigation of the low-lying states of the C2- ion, Chem. Phys. Lett., 1974, 26, 144. [all data]

Cathro and Mackie, 1973
Cathro, W.S.; Mackie, J.C., Oscillator strength of the C2-B2«SIGMA» - X2«SIGMA» transition: a shock-tube determination, J. Chem. Soc. Faraday Trans. 2, 1973, 69, 237. [all data]

Milligan and Jacox, 1969
Milligan, D.E.; Jacox, M.E., Studies of the photoproduction of electrons in inert solid matrices. The electronic spectrum of the species C2-, J. Chem. Phys., 1969, 51, 1952. [all data]

Frosch, 1971
Frosch, R.P., C2 and C2- spectra produced by the X irradiation of acetylene in rare-gas matrices, J. Chem. Phys., 1971, 54, 2660. [all data]

Bondybey and Nibler, 1972
Bondybey, V.; Nibler, J.W., Laser excited fluorescence studies of matrix isolated C2-, J. Chem. Phys., 1972, 56, 4719. [all data]

Brus and Bondybey, 1975
Brus, L.E.; Bondybey, V.E., Molecular ions and electron transport in rare gas lattices: C2- formation mechanism and X2«SIGMA»g+ = B2«SIGMA»u+ spectroscopy, J. Chem. Phys., 1975, 63, 3123. [all data]

Singh and Maheshwari, 1971
Singh, I.D.; Maheshwari, R.C., Isotope/effect on Franck-Condon factors & r-centroids for the new (1«SIGMA»u+-1«SIGMA»g+) system of isotopic C2 molecule, Indian J. Pure Appl. Phys., 1971, 9, 296. [all data]

Feldman, 1970
Feldman, D., Photoablosung von Elektronen bei einigen Stabilen Negativen Ionen, Z. Naturfor., 1970, 25A, 621. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, References