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Argon dimer

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: K.P. Huber and G. Herzberg

Data collected through December, 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 40Ar2
Unclassified, mostly diffuse absorption bands in the region 88100 -90100, 106600 - 108200, 113000 - 1139000, 114900 - 127200 cm-1.
Wilkinson, 1968; Tanaka and Yoshino, 1970
            (117666) 1
Tanaka and Yoshino, 1970
H  [128.4] 1 2 H 3         H larrow X V 112033.9 1 2 H
Tanaka and Yoshino, 1970
G  [170.5] 1 2 H         G larrow X V 110930.9 1 2 H
missing citation
F (0u+)  [134.2] 1 H         F larrow X V 108492.2 1 H
Tanaka and Yoshino, 1970
E  [170] 1 H 4         E larrow X V 107330 1 H
Tanaka and Yoshino, 1970
D  [183.2] 1 H 4         D larrow X V 106029.5 1 H
Tanaka and Yoshino, 1970
C (0u+) 95033 67.0 H 4.03 5        C larrow X V 95050.7 H
missing citation
B (1Sigmau+) 0u+  [136.49] 6 Z   [0.1057] 6   [0.0000007] 6  [2.825] 6 B larrow X V 9324l.26 6 Z
missing citation; Colbourn and Douglas, 1976
A (3Sigmau+) 1u  [133.7] 1 H 7        A lrarrow X V 92393.3 1 H
missing citation
           A,B rarrow X 
missing citation; missing citation; Huffman, Larrabee, et al., 1965; Wilkinson, 1967
Additional continua at 65000, 53000, 47000 cm-1 Tanaka, 1955, Strickler and Arakawa, 1964, Verkhovtseva, Fogel, et al., 1968, Hurst, Bortner, et al., 1969, and diffuse emission bands in the region 87000 - 89000 cm-1 Tanaka, 1955, Tanaka, Jursa, et al., 1958.
X 1Sigmag+ 0 [25.74] Z 8  0.05975 0.00375 -0.000313 [0.00000113] 9  3.758 10 
Docken and Schafer, 1973; Colbourn and Douglas, 1976


1Lowest observed level and interval; vibrational numbering unknown.
2The vibrational levels assigned to G and H may belong to a single state with omegae geq176; omegaexe ~2.85.
3Long upper state progressions.
4All bands appear diffuse.
5This state correlates with 4s'[1/2]1 + 1S .
6Constants for the lowest of four rotationally analyzed levels Colbourn and Douglas, 1976; vibrational numbering unknown, Michaelson and Smith, 1974 estimate v=22. This state correlates with 4s[3/2]1 + 1S and may have a potential hump of ~ 70 cm-1 Tanaka and Yoshino, 1970.
7Rapid convergence to the limit 4s[3/2]2 + 1S
8DeltaG(3/2,...,9/2) = 20.41, 15.60, 10.91, 6.78. G(0) = 14.80.
9Delta1(E-7cm-1) =16.6, Delta2(E-7cm-1)= 20, Delta3(E-7cm-1)= 33, Delta4(E-7cm-1)= 52, Delta5(E-7cm-1)= 200.
10Raman spectrum Morgan and Frommhold, 1972, missing citationa, Frommhold and Bain, 1975.
11Calculated by Colbourn and Douglas, 1976 from spectroscopic data for the five lowest vibrational levels in X 1Sigmag+ and using information from long-range forces and from the second virial coefficient. De = 99.55 cm-1; compare with earlier results by Cavallini, Gallinaro, et al., 1970, Barker, Fisher, et al., 1971, Maitland and Smith, 1971, Parson, Siska, et al., 1972, LeRoy, 1972, Present, 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.

Wilkinson, 1968
Wilkinson, P.G., Absorption spectrum of argon in the 1070-1135 Å region, Can. J. Phys., 1968, 46, 315. [all data]

Tanaka and Yoshino, 1970
Tanaka, Y.; Yoshino, K., Absorption spectrum of the argon molecule in the vacuum-UV region, J. Chem. Phys., 1970, 53, 2012. [all data]

Colbourn and Douglas, 1976
Colbourn, E.A.; Douglas, A.E., The spectrum and ground state potential curve of Ar2, J. Chem. Phys., 1976, 65, 1741. [all data]

Huffman, Larrabee, et al., 1965
Huffman, R.E.; Larrabee, J.C.; Tanaka, Y., Rare gas continuum light sources for photoelectric scanning in the vacuum ultraviolet, Appl. Opt., 1965, 4, 1581. [all data]

Wilkinson, 1967
Wilkinson, P.G., The mechanism of the argon emission continuum in the vacuum ultraviolet. I, Can. J. Phys., 1967, 45, 1715. [all data]

Tanaka, 1955
Tanaka, Y., Continuous emission spectra of rare gases in the vacuum ultraviolet region, J. Opt. Soc. Am., 1955, 45, 710. [all data]

Strickler and Arakawa, 1964
Strickler, T.D.; Arakawa, E.T., Optical emission from argon excited by alpha particles: quenching studies, J. Chem. Phys., 1964, 41, 1783. [all data]

Verkhovtseva, Fogel, et al., 1968
Verkhovtseva, E.T.; Fogel, Ya.M.; Osyka, V.S., On the continuous spectra of inert gases in the vacuum-ultraviolet region obtained by means of a gas-jet source, Opt. Spectrosc. Engl. Transl., 1968, 25, 238, In original 440. [all data]

Hurst, Bortner, et al., 1969
Hurst, G.S.; Bortner, T.E.; Strickler, T.D., Proton excitation of the argon atom, Phys. Rev., 1969, 178, 4. [all data]

Tanaka, Jursa, et al., 1958
Tanaka, Y.; Jursa, A.S.; LeBlanc, F.J., Continuous emission spectra of rare gases in the vacuum ultraviolet region. II. Neon and helium, J. Opt. Soc. Am., 1958, 48, 304. [all data]

Docken and Schafer, 1973
Docken, K.K.; Schafer, T.P., Spectroscopic information on ground-state Ar2, Kr2, and Xe2 from interatomic potentials, J. Mol. Spectrosc., 1973, 46, 454. [all data]

Michaelson and Smith, 1974
Michaelson, R.C.; Smith, A.L., Potential curves from emission continua. IV. The upper state of the vacuum uv contiua of Ar2, J. Chem. Phys., 1974, 61, 2566. [all data]

Morgan and Frommhold, 1972
Morgan, C.E.; Frommhold, L., Raman spectra of van der Waals dimers in argon, Phys. Rev. Lett., 1972, 29, 1053. [all data]

Frommhold and Bain, 1975
Frommhold, L.; Bain, R., Comments concerning the "Raman spectra of van der Waals dimers in argon", J. Chem. Phys., 1975, 63, 1700. [all data]

Cavallini, Gallinaro, et al., 1970
Cavallini, M.; Gallinaro, G.; Meneghetti, L.; Scoles, G.; Valbusa, U., Rainbow scattering and the intermolecular potential of argon, Chem. Phys. Lett., 1970, 7, 303. [all data]

Barker, Fisher, et al., 1971
Barker, J.A.; Fisher, R.A.; Watts, R.O., Liquid argon: Monte Carlo and molecular dynamics calculations, Mol. Phys., 1971, 21, 657. [all data]

Maitland and Smith, 1971
Maitland, G.C.; Smith, E.B., The intermolecular pair potential of argon, Mol. Phys., 1971, 22, 861. [all data]

Parson, Siska, et al., 1972
Parson, J.M.; Siska, P.E.; Lee, Y.T., Intermolecular potentials from crossed-beam differential elastic scattering measurements. IV. Ar + Ar, J. Chem. Phys., 1972, 56, 1511. [all data]

LeRoy, 1972
LeRoy, R.J., Improved spectroscopic dissociation energy for ground-state Ar2, J. Chem. Phys., 1972, 57, 573. [all data]

Present, 1973
Present, R.D., Collision diameter and well depth of the Ar-Ar interaction, J. Chem. Phys., 1973, 58, 2659. [all data]


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