Dihelium

• Formula: He₂
• Molecular weight: 8.005204
• IUPAC Standard InChI: InChI=1S/He2/c1-2 Copy

  
• IUPAC Standard InChIKey: GHVQTHCLRQIINU-UHFFFAOYSA-N Copy
• CAS Registry Number: 12184-98-4
• Chemical structure:
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• Information on this page:
  • Constants of diatomic molecules
  • References
  • Notes
• Other data available:
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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, 1976

Notes

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.

Ginter and Ginter, 1968
Ginter, M.L.; Ginter, D.S., Spectrum and structure of the He₂ molecule. V. Characterization of the triplet states associated with the UAO's 6-17pπ and 7-12pσ, J. Chem. Phys., 1968, 48, 2284. [all data]

Rosen, 1970
Rosen, B., International tables of selected constants. 17. Spectroscopic data relative to diatomic molecules, Pub. Pergamon Press, Oxford, 1970, 0. [all data]

Dieke, 1929
Dieke, G.H., Uber die eigenschaften einer klasse von molekultermen, insbesondere der terme des heliummolekuls, Z. Phys., 1929, 57, 71. [all data]

Dieke, Imanishi, et al., 1929
Dieke, G.H.; Imanishi, S.; Takamine, T., Neue gesetzmabigkeiten im bandenspektrum des heliums. III, Z. Phys., 1929, 57, 305. [all data]

Jevons, 1932
Jevons, W., Report on band-spectra of diatomic molecules, Pub. The Physical Society, The University Press, London, 1932, 0. [all data]

Orth and Ginter, 1976
Orth, F.B.; Ginter, M.L., The spectrum and structure of the He₂ molecule. Characterization of the triplet states associated with the UAO's 4pσ, 5pσ, and 6pσ, J. Mol. Spectrosc., 1976, 61, 282. [all data]

Brown and Ginter, 1973
Brown, C.M.; Ginter, M.L., Spectrum and structure of the He₂ molecule. Characterization of the singlet and triplet states associated with the UAO'S 4s, 4dσ, 4dπ, and 4dδ, J. Mol. Spectrosc., 1973, 46, 256. [all data]

Ginter, 1966
Ginter, M.L., Spectrum and structure of the He₂ molecule. IV. Characterization of the singlet and triplet states associated with the UAO's 3dσ, 3dπ, and 3dδ, J. Chem. Phys., 1966, 45, 248. [all data]

Ginter, 1965
Ginter, M.L., The spectrum and structure of the He₂ molecule. Part III. Characterization of the triplet states associated with the UAO's 3s and 2pπ, J. Mol. Spectrosc., 1965, 18, 321. [all data]

Brown and Ginter, 1971
Brown, C.M.; Ginter, M.L., Spectrum and structure of the He₂ molecule. VI. Characterization of the states associated with the UAO's 3pπ and 2s, J. Mol. Spectrosc., 1971, 40, 302. [all data]

Ginter, 1965, 2
Ginter, M.L., Spectrum and structure of the He₂ molecule. I. Characterization of the states associated with the UAO's 3pσ and 2s, J. Chem. Phys., 1965, 42, 561. [all data]

Hepner and Herman, 1956
Hepner, G.; Herman, L., Spectroscopie. Nouveau systeme de bandes d'emission de la molecule He₂ vers 4700 cm^-1, C.R. Acad. Sci. Paris, Ser. B, 1956, 243, 1504. [all data]

Gloersen and Dieke, 1965
Gloersen, P.; Dieke, G.H., Molecular spectra of hydrogen and helium in the infrared, J. Mol. Spectrosc., 1965, 16, 191. [all data]

Ginter, 1965, 3
Ginter, M.L., The spectrum and structure of the He₂ molecule. Part II. Characterization of the singlet states associated with the UAO's 3s and 2pπ, J. Mol. Spectrosc., 1965, 17, 224. [all data]

Tanaka and Yoshino, 1963
Tanaka, Y.; Yoshino, K., 600-Å band of helium, J. Chem. Phys., 1963, 39, 3081. [all data]

Mies and Smith, 1966
Mies, F.H.; Smith, A.L., Bandlike structure from continuum-continuum emission: the He₂ 600-Å bands, J. Chem. Phys., 1966, 45, 994. [all data]

Smith, 1967
Smith, A.L., Observing the effect of a change in mass on de Broglie wavelength: the 600-Å bands of ³He₂, J. Chem. Phys., 1967, 47, 1561. [all data]

Chow, Smith, et al., 1971
Chow, K.W.; Smith, A.L.; Waggoner, M.G., Absorption coefficients of helium between 599 and 610 Å; transition moment for He₂ A¹ Σ_u⁺ ← X¹ Σ_g⁺, J. Chem. Phys., 1971, 55, 4208. [all data]

Browne, 1965
Browne, J.C., Quantum mechanical potential energy curves for the ¹Π_u and ³Π_u states of He₂ and the ¹Π_g and ³Π_g states of H₂, Phys. Rev. A: Gen. Phys., 1965, 138, 9. [all data]

Gupta and Matsen, 1969
Gupta, B.K.; Matsen, F.A., Quantum-mechanical study of the F¹Π_u and f³Π_u states of He₂, J. Chem. Phys., 1969, 50, 3797. [all data]

Mulliken, 1964
Mulliken, R.S., Rare-gas and hydrogen molecule electronic states, noncrossing rule, and recombination of electrons with rare-gas and hydrogen ions, Phys. Rev., 1964, 136, 962. [all data]

Dieke and Robinson, 1950
Dieke, G.H.; Robinson, E.S., The molecular spectrum of He³, Phys. Rev., 1950, 80, 1. [all data]

Callear and Hedges, 1967
Callear, A.B.; Hedges, R.E.M., Metastability of rotationally hot dihelium at 77° K, Nature (London), 1967, 215, 1267. [all data]

Ludlum, Larson, et al., 1967
Ludlum, K.H.; Larson, L.P.; Caffrey, J.M., Jr., Activation energy for the three-body reaction of helium triplet atom with normal helium, J. Chem. Phys., 1967, 46, 127. [all data]

Ginter and Battino, 1970
Ginter, M.L.; Battino, R., Potential-energy curves for the He₂ molecule, J. Chem. Phys., 1970, 52, 4469. [all data]

Poshusta and Matsen, 1963
Poshusta, R.D.; Matsen, F.A., Potential curve of the metastable helium molecule, Phys. Rev., 1963, 132, 307. [all data]

Klein, Greenawalt, et al., 1967
Klein, D.J.; Greenawalt, E.M.; Matsen, F.A., Adjustment of ab initio potential curves, J. Chem. Phys., 1967, 47, 4820. [all data]

Gupta, 1972
Gupta, B.K., On the potential curve of the metastable helium molecule, Mol. Phys., 1972, 23, 75. [all data]

Lichten, McCusker, et al., 1974
Lichten, W.; McCusker, M.V.; Vierima, T.L., Fine structure of the metastable a³Σ_u⁺ state of the helium molecule, J. Chem. Phys., 1974, 61, 2200. [all data]

Vierima, 1975
Vierima, T.L., Determination of the sign of the spin-spin interaction in He₂(a³Σ_u⁺), J. Chem. Phys., 1975, 62, 2925. [all data]

Beck, Nicolaides, et al., 1974
Beck, D.R.; Nicolaides, C.A.; Musher, J.I., Calculation of the fine structure of the a³Σ_u⁺ state of molecular helium, Phys. Rev. A: Gen. Phys., 1974, 10, 1522. [all data]

Zhirnov and Shadrin, 1968
Zhirnov, N.I.; Shadrin, O.P., Calculation of Franck-Condon factors with Poschl-Teller wavefunctions. I. The probabilities of some vibrational transitions in the D¹Σ_u⁺-B¹Π_g band system of the He₂ molecule, Opt. Spectrosc. Engl. Transl., 1968, 24, 478, In original 890. [all data]

Chow and Smith, 1971
Chow, K.-W.; Smith, A.L., Repulsive potential curves from molecular continuum-continuum emission. III. He₂(X¹Σ_g⁺), J. Chem. Phys., 1971, 54, 1556. [all data]

Guberman and Goddard, 1972
Guberman, S.L.; Goddard, W.A., III, On the origin of energy barriers in the excited states of He₂, Chem. Phys. Lett., 1972, 14, 460. [all data]

Andresen and Kuppermann, 1975
Andresen, B.; Kuppermann, A., The scattering of excited by ground state atoms application to He₂, Mol. Phys., 1975, 30, 997. [all data]

Guberman and Goddard, 1975
Guberman, S.L.; Goddard, W.A., III, Nature of the excited states of He₂, Phys. Rev. A: Gen. Phys., 1975, 12, 1203. [all data]

Smith and Chow, 1970
Smith, A.L.; Chow, K.W., RKR potential and more accurate dissociation energy of He₂(A¹Σ_u⁺), J. Chem. Phys., 1970, 52, 1010. [all data]

Mukamel and Kaldor, 1971
Mukamel, S.; Kaldor, U., Potential of the A¹Σ_u⁺ state of He₂, Mol. Phys., 1971, 22, 1107. [all data]

Allison, Browne, et al., 1966
Allison, D.C.; Browne, J.C.; Dalgarno, A., Collision-induced de-activation of metastable helium, Proc. Phys. Soc. London, 1966, 89, 41. [all data]

Scott, Greenawalt, et al., 1966
Scott, D.R.; Greenawalt, E.M.; Browne, J.C.; Matsen, F.A., Quantum-mechanical potential-energy curve for the lowest ¹Σ_u⁺ state of He₂, J. Chem. Phys., 1966, 44, 2981. [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]

Michaelson and Smith, 1970
Michaelson, R.C.; Smith, A.L., Time resolved studies of rare-gas molecular emission in the vacuum ultraviolet: helium and argon, Chem. Phys. Lett., 1970, 6, 1. [all data]

Mukamel and Kaldor, 1973
Mukamel, S.; Kaldor, U., Ab initio calculation of the He₂ A¹Σ_u⁺ ← X¹Σ_g⁺ absorption spectrum, Mol. Phys., 1973, 26, 291. [all data]

Peatman and Wu, 1973
Peatman, W.B.; Wu, D.T., The 600 Å bands of helium, Chem. Phys., 1973, 2, 335. [all data]

Sando and Dalgarno, 1971
Sando, K.M.; Dalgarno, A., The absorption of radiation near 600 Å by helium, Mol. Phys., 1971, 20, 103. [all data]

Miller, Freund, et al., 1975
Miller, T.A.; Freund, R.S.; Zegarski, B.R.; Jost, R.; Lombardi, M.; Derouard, J., Observation of singlet-triplet anticrossings in ⁴He₂, J. Chem. Phys., 1975, 63, 4042. [all data]

Farrar and Lee, 1972
Farrar, J.M.; Lee, Y.T., Intermolecular potentials from crossed beam differential elastic scattering measurements. V. The attractive well of He₂, J. Chem. Phys., 1972, 56, 5801. [all data]

Burgmans, Farrar, et al., 1976
Burgmans, A.L.J.; Farrar, J.M.; Lee, Y.T., Attractive well of He-He from ³He-⁴He differential elastic scattering measurements, J. Chem. Phys., 1976, 64, 1345. [all data]

Bennewitz, Busse, et al., 1972
Bennewitz, H.G.; Busse, H.; Dohmann, H.D.; Oates, D.E.; Schrader, W., Evidence for different interaction potentials for He⁴ - He⁴ and He³ - He³ from scattering cross-section measurements, Phys. Rev. Lett., 1972, 29, 533. [all data]

Schaefer, McLaughlin, et al., 1970
Schaefer, H.F., III; McLaughlin, D.R.; Harris, F.E.; Alder, B.J., Calculation of the attractive He pair potential, Phys. Rev. Lett., 1970, 25, 988. [all data]

McLaughlin and Schaefer, 1971
McLaughlin, D.R.; Schaefer, H.F., III, Interatomic correlation energy and the van der Waals attraction between two helium atoms, Chem. Phys. Lett., 1971, 12, 244. [all data]

Liu and McLean, 1973
Liu, B.; McLean, A.D., Accurate calculation of the attractive interaction of two ground state helium atoms, J. Chem. Phys., 1973, 59, 4557. [all data]

Bertoncini and Wahl, 1970
Bertoncini, P.; Wahl, A.C., Ab initio calculation of the helium-helium ¹Σ_g⁺ potential at intermediate and large separations, Phys. Rev. Lett., 1970, 25, 991. [all data]

Kleinman and Wolfsberg, 1974
Kleinman, L.I.; Wolfsberg, M., Adiabatic correction to the van der Waals well depth of He₂, J. Chem. Phys., 1974, 61, 4366. [all data]

Snook and Spurling, 1975
Snook, I.K.; Spurling, T.H., Symmetry adapted perturbation theory of intermolecular potentials. The helium-helium interaction, J. Chem. Soc. Faraday Trans. 2, 1975, 71, 852. [all data]

Murrell, 1969
Murrell, J.N., Bound vibrational states for weakly attractive potentials, Mol. Phys., 1969, 16, 601. [all data]

Poulat, Larsen, et al., 1975
Poulat, C.; Larsen, S.Y.; Novaro, O., Is there a helium molecule?, Mol. Phys., 1975, 30, 645. [all data]

Chapman, 1975
Chapman, R., Temperature dependence of the relaxation time in dilute ³He gas: an investigation of the He-He potential, Phys. Rev. A: Gen. Phys., 1975, 12, 2333. [all data]

Foreman, Rol, et al., 1974
Foreman, P.B.; Rol, P.K.; Coffin, K.P., The repulsive ¹Σ_g⁺ He₂ potential obtained from total cross sections, J. Chem. Phys., 1974, 61, 1658. [all data]

Alexander, 1970
Alexander, M.H., Exact treatment of the long-range dipole-dipole interaction between two helium atoms, J. Chem. Phys., 1970, 52, 3354. [all data]

Bruch and McGee, 1970
Bruch, L.W.; McGee, I.J., Semiempirical helium intermolecular potential. II. Dilute gas properties, J. Chem. Phys., 1970, 52, 5884. [all data]

Ginter and Brown, 1972
Ginter, M.L.; Brown, C.M., Dissociation energies of X²Σ_u⁺ (HE₂⁺) and A¹Σ_u⁺ (He₂), J. Chem. Phys., 1972, 56, 672. [all data]

Notes

Go To: Top, Constants of diatomic molecules, References

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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