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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 April, 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 11B2H
H 1Delta 3d     [6.635]     [1.2216] H larrow X 66448.0 Z
missing citation
G 1Pi 3d     [6.635]     [1.2216] G larrow X 66362.8 Z
missing citation
F 1Sigma+ 3d     [6.635]     [1.2216] F larrow X 66068.6 Z
missing citation
E 1Sigma+ 3p     [6.736]   [0.4E-3]  [1.2124] E larrow X 61852.8 Z
missing citation
D 1Pi 3p     [6.736]   0.4E-3  [1.2124] D larrow X 61110.2 Z
missing citation
B 1Sigma+ 3s 52348 1 [1700.34] Z 46.6  6.705 0.195 2  0.4E-3 3  1.2152 B larrow X 4 52360.21 Z
missing citation
A 1Pi 23142 [1594.08] Z (43)  6.648 5 0.280  0.403E-3 6  1.2204 A rarrow X VR 23098.75 Z
Thunberg, 1936; Bauer, Herzberg, et al., 1964
X 1Sigma+ 0 [1703.26] Z (28)  6.542 0.171  0.42 7  1.2302  


1Large electronic isotope shift; see Bunker, 1968.
2missing note
3H0 = +0.35E-9.
4Headless bands.
5Thunberg's Thunberg, 1936 value of 6.653 was derived from R and P branches only; Deltavef = +0.0102J(J+1).
6missing note
7missing note
8From the value for BH.


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

Thunberg, 1936
Thunberg, S.F., Untersuchung uber die bandenspektra von borhydrid und bordeutrid, Z. Phys., 1936, 100, 471. [all data]

Bauer, Herzberg, et al., 1964
Bauer, S.H.; Herzberg, G.; Johns, J.W.C., The absorption spectrum of BH and BD in the vacuum ultraviolet, J. Mol. Spectry., 1964, 13, 256. [all data]

Bunker, 1968
Bunker, P.R., The electronic isotope shift in diatomic molecules and the partial breakdown of the Born-Oppenheimer approximation, J. Mol. Spectrosc., 1968, 28, 422. [all data]


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