Argon

• Formula: Ar
• Molecular weight: 39.948
• IUPAC Standard InChI: InChI=1S/Ar Copy

  
• IUPAC Standard InChIKey: XKRFYHLGVUSROY-UHFFFAOYSA-N Copy
• CAS Registry Number: 7440-37-1
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: Ar; UN 1006; UN 1951; argon atom
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• Information on this page:
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 100, reactions 101 to 102
  • Henry's Law data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • Fluid Properties
• Data at other public NIST sites:
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  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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Gas phase ion energetics data

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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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

References

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

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

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Weitzel, Mahnert, et al., 1994
Weitzel, K.-M.; Mahnert, J.; Penno, M., ZEKE-PEPICO investigations of dissociation energies in ionic reactions, Chem. Phys. Lett., 1994, 224, 371. [all data]

Lide, 1992
Lide, D.R. (Editor), Ionization potentials of atoms and atomic ions in Handbook of Chem. and Phys., 1992, 10-211. [all data]

Wetzel, Baiocchi, et al., 1987
Wetzel, R.C.; Baiocchi, F.A.; Hayes, T.R.; Freund, R.S., Absolute cross sections for electron-impact ionization of the rare-gas atoms by the fast-neutral-beam method, Phys. Rev. A, 1987, 35, 559. [all data]

Kelly, 1987
Kelly, R.L., Atomic and ionic spectrum lines of hydrogen through kryton, J. Phys. Chem. Ref. Data, 1987, 16. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Clare and Sowerby, 1981
Clare, P.; Sowerby, D.B., Electron impact ionisation energies of some halo-cyclotriphosphazenes, J. Inorg. Nucl. Chem., 1981, 43, 477. [all data]

Freiser, 1980
Freiser, B.S., Electron impact ionization of argon ions by trapped ion cyclotron resonanace spectroscopy, Int. J. Mass Spectrom. Ion Phys., 1980, 33, 263. [all data]

Minnhagen, 1973
Minnhagen, L., Spectrum and the energy levels of neutral argon, Ar I, J. Opt. Soc. Am., 1973, 63, 1185. [all data]

Spohr, Guyon, et al., 1971
Spohr, R.; Guyon, P.M.; Chupka, W.A.; Berkowitz, J., Threshold photoelectron detector for use in the vacuum ultraviolet, Rev. Sci. Instrum., 1971, 42, 1872. [all data]

Yoshino, 1970
Yoshino, K., Absorption spectrum of the argon atom in the vacuum-ultraviolet region, J. Opt. Soc. Am., 1970, 60, 1220. [all data]

Yoshino, 1969
Yoshino, K., Absorption spectrum of the argon atom in the vacuum-ultraviolet region, J. Opt. Soc. Am., 1969, 59, 1525. [all data]

Hotop and Niehaus, 1969
Hotop, H.; Niehaus, A., Reactions of excited atoms molecules with atoms and molecules. II. Energy analysis of penning electrons, Z. Phys., 1969, 228, 68. [all data]

Collin and Natalis, 1968
Collin, J.E.; Natalis, P., Vibrational and electronic ionic states of nitric oxide. An accurate method for measuring ionization potentials by photoelectron spectroscopy, Intern. J. Mass Spectrom. Ion Phys., 1968, 1, 483. [all data]

Gallegos and Klaver, 1967
Gallegos, E.J.; Klaver, R.F., Automatic voltage scanner for a peak switching mass spectrometer, J.Sci. Instr., 1967, 44, 427. [all data]

Winters, Collins, et al., 1966
Winters, R.E.; Collins, J.H.; Courchene, W.L., Resolution of fine structure in ionization-efficiency curves, J. Chem. Phys., 1966, 45, 1931. [all data]

Al-Joboury and Turner, 1963
Al-Joboury, M.I.; Turner, D.W., Molecular photo-electron spectroscopy. Part I. The hydrogen and nitrogen molecules, J. Chem. Soc., 1963, 5141. [all data]

Notes

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

• Symbols used in this document:
  

  IE (evaluated)

  Recommended ionization energy

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