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Argon, compound with helium (1:1)

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 September, 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 4He40Ar
X 1Sigma+ 0 1         3.51 2 3 
Bosomworth and Gush, 1965


1Only v=0 is bound; see Bobetic and Barker, 1976
2From molecular beam scattering measurements; average of values given by Chen, Siska, et al., 1973 and Smith, Rulis, et al., 1975.
3Dipole moment function from ab initio calculations Matcha and Nesbet, 1967 and from translational absorption spectra Bar-Ziv and Weiss, 1973.


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.

Bosomworth and Gush, 1965
Bosomworth, D.R.; Gush, H.P., Collision-induced absorption of compressed gases in the far infrared, Part II, Can. J. Phys., 1965, 43, 751. [all data]

Bobetic and Barker, 1976
Bobetic, M.V.; Barker, J.A., Vibrational levels of heteronuclear rare gas van der Waals molecules, J. Chem. Phys., 1976, 64, 2367-2369. [all data]

Chen, Siska, et al., 1973
Chen, C.H.; Siska, P.E.; Lee, Y.T., Intermolecular potentials from crossed beam differential elastic scattering measurements. VIII. He+Ne, He+Ar, He+Kr, and He+Xe, J. Chem. Phys., 1973, 59, 2, 601-610. [all data]

Smith, Rulis, et al., 1975
Smith, K.M.; Rulis, A.M.; Scoles, G.; Aziz, R.A.; Duquette, G., Intermolecular forces in gaseous mixtures: He-Ar, J. Chem. Phys., 1975, 63, 5, 2250-2252. [all data]

Matcha and Nesbet, 1967
Matcha, R.L.; Nesbet, R.K., Electric dipole moments of rare-gas diatomic molecules, Phys. Rev., 1967, 160, 1, 72-75. [all data]

Bar-Ziv and Weiss, 1973
Bar-Ziv, E.; Weiss, S., Dipole moment of interacting rare-gas atoms, Chem. Phys. Lett., 1973, 19, 1, 148-151. [all data]


Go To: Top, Constants of diatomic molecules, References