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:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Information on this page:
  • Gas phase ion energetics data
  • Constants of diatomic molecules
  • References
  • Notes
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Gas phase ion energetics data

Go To: Top, Constants of diatomic molecules, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

Constants of diatomic molecules

Go To: Top, Gas phase ion energetics data, 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 November, 1976

Notes

References

Go To: Top, Gas phase ion energetics data, 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.

Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979, ,1. [all data]

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, Gas phase ion energetics data, Constants of diatomic molecules, References

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