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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 July, 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 (64)Zn127I
E 44115 142 H 3        E rarrow X R 44073 H
Ramasastry, 1948
D (39911) (80) 1 H (1.3)        D rarrow X (39839) 1 H
Ramasastry, 1949
C2 (2Pi) 30125.8 2 248.2 H 0.72        C2 lrarrow X 3 V 30138.2 2 H
Wieland, 1929; missing citation
C1 29498.9 272.0 H 0.50        C1 larrow X V 29523.2 H
missing citation
B (2Sigma) 4           B rarrow X R 
Terenin, 1927; Wieland, 1929; Oeser, 1935; Wieland, 1948
X (2Sigma) 0 223.4 H 0.63 5         


1Only bands with v" geq 15 and v' leq 2; neither the analysis nor the assignment to ZnI appear certain.
2Wieland Wieland, 1929 gives Te ~ 30117.6 Wieland, 1929, nu00 = 30129.5 Wieland, 1929.
3According to Gosavi, Greig, et al., 1971 most of the diffuse emission bands of system D of Rao and Rao, 1946 in the region 30500 - 31300 cm-1 fit well into the C2-X system.
4Bands in the region 16000 - 28600 cm-1; no analysis.
5Average value from C1-X and C2-X.


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.

Ramasastry, 1948
Ramasastry, C., Ultra-violet bands of zinc iodide--Part III, Indian J. Phys., 1948, 22, 119. [all data]

Ramasastry, 1949
Ramasastry, C., Ultra-violet bands of the zinc iodide molecule. Part III, Indian J. Phys., 1949, 23, 35. [all data]

Wieland, 1929
Wieland, K., Bandenspektren der quecksilber-, cadmium- und zinkhalogenide, Helv. Phys. Acta, 1929, 2, 46. [all data]

Terenin, 1927
Terenin, A., Optische dissoziation der salzmolekule, Z. Phys., 1927, 44, 713. [all data]

Oeser, 1935
Oeser, E., Absorptions- und Fluoreszenzuntersuchungen an dampfformigen Cadmium und Zinkhalogeniden, Z. Phys., 1935, 47, 699. [all data]

Wieland, 1948
Wieland, K., Molekulspektren mit Ionencharakter und ihre Beeinflussung durch Fremdgase in Contribution a l'Etude de la Structure Moleculaire, Desoer, Liege, ed(s)., 1948, 229-238. [all data]

Gosavi, Greig, et al., 1971
Gosavi, R.K.; Greig, G.; Young, P.J.; Strausz, O.P., Reactions of metal atoms. IV. The UV spectra of CdBr, CdI, ZnBr, and ZnI, J. Chem. Phys., 1971, 54, 983. [all data]

Rao and Rao, 1946
Rao, P.T.; Rao, K.R., Ultra violet bands of zinc iodide. Part I, Indian J. Phys., 1946, 20, 49. [all data]


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