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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, 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 133CsH
a (3Delta) [28534] 1 [276] 1   [1.51] 1       
Ringstrom, 1970
B 1Sigma+ [28350.5] 2 [82.1] 2 Z   [0.070] 2     [4.63] B larrow X R 27908.2 2 Z
Ringstrom, 1970
A 1Sigma+ 17845.8 165.7 Z -7.77 3  1.075 -0.0219 4  0.000098 -2.0E-06 3.960 A lrarrow X R 17488.3 Z
Almy and Rassweiler, 1938; Bartky, 1966; Tam and Happer, 1976
X 1Sigma+ 0 891.0 Z 12.93 5 0.105 2.7099 0.0579  [113]  2.4938  


1Constants for the lowest of three levels observed in small perturbations of B 1Sigma+; A~14. Vibrational numbering unknown, Omega = 3 not observed.
2Constants for the lowest of eleven observed levels, v'= 11 ± 3. DeltaG increases to 93.7 for v=18; Bv(v leq 18) = 0.787 - 0.0076(v+1/2). For v > 18 both DeltaG and Bv decrease rapidly.
3omegaexe= -0.297(v+1/2)3 + 0.0040(v+1/2)4 (valid for v leq 15).
4alphav= 0.00131(v+1/2)2; v leq 13.
5omegaeze = -0.0018. Observed up to v" =14 in laser-excited fluorescence Tam and Happer, 1976.
6Short extrapolation of vibrational levels in B 1Sigma+ to the limit 2D + 2S Ringstrom, 1970. A longer extrapolation of the ground state levels Tam and Happer, 1976 gives 2.08 eV.
7From band heads, 8 leq v' leq 18.
8Only the 10-0 and 11-0 bands have been rotationally analyzed Bartky, 1966; B10 = 0.587, B11 = 0.586.
9Band origins for the 10-0 and 11-0 bands at 19091.2 and 19261.8 cm-1.


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

Ringstrom, 1970
Ringstrom, U., A new band system and Klein-Rydberg potential curves of CsH, J. Mol. Spectrosc., 1970, 36, 232. [all data]

Almy and Rassweiler, 1938
Almy, G.M.; Rassweiler, M., The absorption spectrum of caesium hydride, Phys. Rev., 1938, 53, 890. [all data]

Bartky, 1966
Bartky, I.R., The absorption spectrum of cesium deuteride. The A1«SIGMA» state of CsH, J. Mol. Spectrosc., 1966, 21, 25. [all data]

Tam and Happer, 1976
Tam, A.C.; Happer, W., Spectroscopy of the CsH (X1«SIGMA»+) state by laser-excited fluorescence, J. Chem. Phys., 1976, 64, 2456. [all data]


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