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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 March, 1975

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 (58)Ni(79)Br
Large number of R shaded emission bands in the region 20000 - 25600 cm-1. Below are preliminary assignments by Reddy and Rao, 1960:
System alpha1 24326.2 297.0 HR 3.35 1        R 24318.5 2 HR
missing citation; Sundarachary, 1962
System alpha2 23920.3 262 H 3         R 23904.7 H
Reddy and Rao, 1960
System alpha3 23791.1 305.4 HR 0.2 4        R 23786.4 HR
Reddy and Rao, 1960
System beta1 22975.5 293.8 H 2.5 5        R 22960.6 H
missing citation; Sundarachary, 1962
System beta2 22435.9 257 HQ 6         R 22427.4 HQ
missing citation
System gamma  297.5 HQ 1.1 7        R 21779.9 HQ
Reddy and Rao, 1960


1omega"e = 311.6 omega"ex"e = 1.7 R, Q heads 9
2Q head at 24311.9 cm-1.
3omega"e = 293.2 9
4omega"e = 315.0 omega"ex"e = 0.5 R, Q(?) heads. 10
5omega"e = 322.8 omega"ex"e = 1.0 9
6omega"e = 274 10
7omega"e = 323.0 omega"ex"e = 1.2 9
8Thermochemical value (flame photometry) Bulewicz, Phillips, et al., 1961.
9Alternative assignments in Mesnage, 1939, Krishnamurty, 1952.
10Alternative assignments in Mesnage, 1939, Krishnamurty, 1952, Sundarachary, 1962.


Go To: Top, 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.

Reddy and Rao, 1960
Reddy, S.P.; Rao, P.T., The band spectra of NiCl and NiBr in the visible, Proc. Phys. Soc. London, 1960, 75, 275. [all data]

Sundarachary, 1962
Sundarachary, N., Emission spectrum of NiBr, Proc. Natl. Acad. Sci. India Sect. A, 1962, 32, 311-319. [all data]

Bulewicz, Phillips, et al., 1961
Bulewicz, E.M.; Phillips, L.F.; Sugden, T.M., Determination of dissociation constants and heats of formation of simple molecules by flame photometry. Part 8. Stabilities of the gaseous diatomic halides of certain metals, Trans. Faraday Soc., 1961, 57, 921. [all data]

Mesnage, 1939
Mesnage, P., Recherches sur les decharges de haute frequence et leur application a la spectroscopie moleculaire, Ann. Phys. (Paris), 1939, 12, 5. [all data]

Krishnamurty, 1952
Krishnamurty, V.G., The complex band spectrum of nickel bromide (NiBr), Indian J. Phys., 1952, 26, 429. [all data]


Go To: Top, Constants of diatomic molecules, References