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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, 1977

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 (205)Tl(79)Br+
The following states are from the photoelectron spectrum Berkowitz, 1972, using vertical potentials for A and B and the adiabatic potential for X 2Pi. The peak corresponding to the shallow 2Pi state is very broad and has a vertical potential which lies at ~ 0.35 eV above that of A 2Sigma.
B 2Sigma (36500)           
A 2Sigma (2700)           
X 2Pi 0           


1Photoionization mass-spectrometry Berkowitz and Walter, 1968. In good agreement with spectroscopic and thermochemical results Barrow, 1960, flame photometry Bulewicz, Phillips, et al., 1961, and electron impact mass- spectrometry Khvostenko and Sultanov, 1965.
2Photoionization value Berkowitz and Walter, 1968. Notice that this is the adiabatic value corresponding to the second vertical potential (9.83 eV) observed in the photoelectron spectrum Berkowitz, 1972; first vertical I.P. at 9.48 eV.
3Absorption cross sections have been measured by missing citation.
4 Howell and Coulson, 1941 report emission continua with maxima at 30020 and 33770 cm-1.
5Assigned by analogy with TlCl; Howell and Coulson, 1941 assume 3Pi1.
6 Lovas and Tiemann, 1974 give rotational constants for four isotopes.
7In argon at 10 K.
8Dipole moment of 205Tl79Br: muel(v=0) =4.49 D Tiemann, 1971, from Stark effect of rotation sp. Tiemann, 1971.
9Hfs constants for four isotopes in the first five vibrational states.
10D00(TlBr) + I.P.(Tl) - I.P.(TlBr).


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.

Berkowitz, 1972
Berkowitz, J., Photoelectron spectroscopy of high-temperature vapors. I. TlCl, TlBr, and TlI, J. Chem. Phys., 1972, 56, 2766. [all data]

Berkowitz and Walter, 1968
Berkowitz, J.; Walter, T.A., Photoionization of high-temperature vapors. IV.TIF, TICI, and TIBr, J. Chem. Phys., 1968, 49, 1184. [all data]

Barrow, 1960
Barrow, R.F., Dissociation energies of the gaseous monohalides of boron, aluminium, gallium, indium, and thallium, Trans. Faraday Soc., 1960, 56, 952. [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]

Khvostenko and Sultanov, 1965
Khvostenko, V.I.; Sultanov, A.Sh., Ionisation of thallium(I) chloride, bromide, and iodide molecules by electron bombardment, Russ. J. Phys. Chem. Engl. Transl., 1965, 39, 252, In original 475. [all data]

Howell and Coulson, 1941
Howell, H.G.; Coulson, N., The band spectrum of thallium bromide, Proc. Phys. Soc. London, 1941, 53, 706. [all data]

Lovas and Tiemann, 1974
Lovas, F.J.; Tiemann, E., Microwave spectral tables. I. Diatomic molecules, J. Phys. Chem. Ref. Data, 1974, 3, 609. [all data]

Tiemann, 1971
Tiemann, E., Elektrisches Dipolmoment von TlBr und TlJ, Z. Naturforsch. A, 1971, 26, 1809. [all data]


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