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Constants of diatomic molecules

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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: Klaus P. Huber and Gerhard H. Herzberg

Data collected through May, 1976

Symbols used in the table of constants
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 14N2++
Following the early work of Hurley, 1962, Thulstrup and Andersen, 1975 have recently given the results of detailed calculations of many low-lying singlet and triplet states. On the basis of this theoretical work the assignment of the observed transition to N2++ seems very probable but not conclusive.
D 1Sigmau+ (62928) (1910) 1   [1.8644]   [7.1E-6]  [1.1364] D rarrow X 62903.18 Z
missing citation; Carroll and Hurley, 1961
A few intermediate states are suggested by Auger electron Stalherm, Cleff, et al., 1969 and double charge transfer spectra Appell, Durup, et al., 1973.
X 1Sigmag+ 2 0 (1960) 1   [1.8801]   [6.9E-6]  [1.1317]  


1Estimated from (4B3/D)1/2.
2Not certain that this is the ground state. As for C2, a low-lying 3Piu state has been predicted Thulstrup and Andersen, 1975.


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

Hurley, 1962
Hurley, A.C., Potential energy curves for doubly positive diatomic ions. Part II. Predicted states and transitions of N22+, O22+, and NO22+, J. Mol. Spectrosc., 1962, 9, 18. [all data]

Thulstrup and Andersen, 1975
Thulstrup, E.W.; Andersen, A., Configuration interaction studies of bound, low-lying states of N2-, N2, N2+ and N22+, J. Phys. B:, 1975, 8, 965. [all data]

Carroll and Hurley, 1961
Carroll, P.K.; Hurley, A.C., Identification of an electronic transition of N22+, J. Chem. Phys., 1961, 35, 2247. [all data]

Stalherm, Cleff, et al., 1969
Stalherm, D.; Cleff, B.; Hillig, H.; Mehlhorn, W., Energies of excited states of doubly ionized molecules by means of auger electron spectroscopy. Part I. Electronic states of N22+, Z. Naturforsch. A, 1969, 24, 1728. [all data]

Appell, Durup, et al., 1973
Appell, J.; Durup, J.; Fehsenfeld, F.C.; Fournier, P., Double charge transfer spectroscopy of diatomic molecules, J. Phys. B:, 1973, 6, 197. [all data]


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