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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 November, 1974

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 (114)CdD
D  [1056] H         D larrow X V 44117 H
Breckenridge and Callear, 1971
C 2Sigma+  [1149] H (37)        C larrow X V 40260 H
Khan, 1962; missing citation
A 2Pi3/2 1 [1209.7] Z   3.086 0.070  0.000073  1.6614 A larrow X V 23236.4 Z
Svensson, 1935; Deile, 1937
A 2Pi1/2     [3.025]   [0.000057]  [1.6780] A larrow X V 22230.1 Z 2
Svensson, 1935; Deile, 1937
X 2Sigma+ 0    [2.704] 3 3  [0.000076] 3  [1.7748]  


1A0= +1012.4.
2J'=1/2 above N"=0. Svensson Svensson, 1935 uses a different definition.
3B1= 2.536, D1= 1.78E-4. Spin doubling Delta nu12(v=0)~ +0.31(N+1/2) - ... Svensson, 1935, Veseth, 1970.
4Short extrapolation of the ground state.
5All observed levels diffuse due to predissociation.
6Observed up to v=13. More accurate constants will depend on the analysis of numerous perturbations by A 2Pi.
7A0= +1012.8, A1= +1016.2.
8Lambda-type doubling; Deltanufe(v=0) = +0.62(J+1/2) - ... Mulliken and Christy, 1931.
9DeltaG (3/2,...,9/2) = 1213.10, 1065.84, 881.10, 635.2. Estimated zero point energy ~ 708.
10Spin doubling Delta nu12(v=0) = +0.60(N+1/2) - ... Mulliken and Christy, 1931, Svensson, 1935, Veseth, 1970. gamma decreases rapidly with increasing v.
11 B1= 5.065, B2= 4.758, B3= 4.388, B4= 3.893, B5= 3.114.
12 D1(E-4 cm-1)= 3.38, D2(E-4 cm-1)= 3.63, D3(E-4 cm-1)= 5.00, D4(E-4 cm-1)= 7.00, D5(E-4 cm-1)= 16.00.
13In Ar matrix at 4 K Knight and Weltner, 1971.


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.

Breckenridge and Callear, 1971
Breckenridge, W.H.; Callear, A.B., Flash spectroscopy with 2288 Å and 3261 Å cadmium resonance radiation. Part 1. An experimental technique with a multi-electrode flash-lamp and some preliminary results, Trans. Faraday Soc., 1971, 67, 2009. [all data]

Khan, 1962
Khan, M.A., A new band system in CdH and CdD, Proc. Phys. Soc. London, 1962, 80, 1264. [all data]

Svensson, 1935
Svensson, Disseration, Stockholm, 1935, 0. [all data]

Deile, 1937
Deile, O., Uber den rotationsisotopieeffekt im bandenspektrum cadmiumhydrid-deuterid, Z. Phys., 1937, 106, 405. [all data]

Veseth, 1970
Veseth, L., Modifications of the doublet energy formulae of a diatomic molecule necessitated by the rotational stretching, J. Phys. B:, 1970, 3, 1677. [all data]

Mulliken and Christy, 1931
Mulliken, R.S.; Christy, A., «LAMBDA»-type doubling and electron configurations in diatomic molecules, Phys. Rev., 1931, 38, 87. [all data]

Knight and Weltner, 1971
Knight, L.B., Jr.; Weltner, W., Jr., Hyperfine interaction, chemical bonding, and isotope effect in ZnH, CdH, and HgH molecules, J. Chem. Phys., 1971, 55, 2061. [all data]


Go To: Top, Constants of diatomic molecules, References