Argon dimer
- Formula: Ar2
- Molecular weight: 79.896
- IUPAC Standard InChI: InChI=1S/2Ar
- IUPAC Standard InChIKey: XMPZLAQHPIBDSO-UHFFFAOYSA-N
- CAS Registry Number: 12595-59-4
- Chemical structure:
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Constants of diatomic molecules
Go To: Top, References, Notes
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 December, 1975
| Symbol | Meaning |
|---|---|
| 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) |
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 ← X V | 112033.9 1 2 H | |||||||||
| ↳Tanaka and Yoshino, 1970 | ||||||||||||
| G | [170.5] 1 2 H | G ← X V | 110930.9 1 2 H | |||||||||
| ↳missing citation | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| F (0u+) | [134.2] 1 H | F ← X V | 108492.2 1 H | |||||||||
| ↳Tanaka and Yoshino, 1970 | ||||||||||||
| E | [170] 1 H 4 | E ← X V | 107330 1 H | |||||||||
| ↳Tanaka and Yoshino, 1970 | ||||||||||||
| D | [183.2] 1 H 4 | D ← X V | 106029.5 1 H | |||||||||
| ↳Tanaka and Yoshino, 1970 | ||||||||||||
| C (0u+) | 95033 | 67.0 H | 4.03 5 | C ← X V | 95050.7 H | |||||||
| ↳missing citation | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| B (1Σu+) 0u+ | [136.49] 6 Z | [0.1057] 6 | [0.0000007] 6 | [2.825] 6 | B ← X V | 9324l.26 6 Z | ||||||
| ↳missing citation; Colbourn and Douglas, 1976 | ||||||||||||
| A (3Σu+) 1u | [133.7] 1 H | 7 | A ↔ X V | 92393.3 1 H | ||||||||
| ↳missing citation | ||||||||||||
| A,B → 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. | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| X 1Σg+ | 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 | ||||||||||||
Notes
| 1 | Lowest observed level and interval; vibrational numbering unknown. |
| 2 | The vibrational levels assigned to G and H may belong to a single state with ωe ≥176; ωexe ~2.85. |
| 3 | Long upper state progressions. |
| 4 | All bands appear diffuse. |
| 5 | This state correlates with 4s'[1/2]1 + 1S . |
| 6 | Constants 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. |
| 7 | Rapid convergence to the limit 4s[3/2]2 + 1S |
| 8 | ΔG(3/2,...,9/2) = 20.41, 15.60, 10.91, 6.78. G(0) = 14.80. |
| 9 | Δ1(E-7cm-1) =16.6, Δ2(E-7cm-1)= 20, Δ3(E-7cm-1)= 33, Δ4(E-7cm-1)= 52, Δ5(E-7cm-1)= 200. |
| 10 | Raman spectrum Morgan and Frommhold, 1972, missing citationa, Frommhold and Bain, 1975. |
| 11 | Calculated by Colbourn and Douglas, 1976 from spectroscopic data for the five lowest vibrational levels in X 1Σg+ 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. |
References
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]
Notes
Go To: Top, Constants of diatomic molecules, References
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