Oxygen, atomic

• Formula: O
• Molecular weight: 15.9994
• IUPAC Standard InChI: InChI=1S/O Copy

  
• IUPAC Standard InChIKey: QVGXLLKOCUKJST-UHFFFAOYSA-N Copy
• CAS Registry Number: 17778-80-2
• Chemical structure:
  This structure is also available as a 2d Mol file
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Ion clustering data
• Data at other public NIST sites:
  • NIST Atomic Spectra Database - Lines Holdings (on physics web site)
  • NIST Atomic Spectra Database - Levels Holdings (on physics web site)
  • NIST Atomic Spectra Database - Ground states and ionization energies (on physics web site)
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Gas Phase Kinetics Database
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Gas phase thermochemistry data

Go To: Top, Reaction thermochemistry data, 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.

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, 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: John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

( • 4294967295) +  =

By formula: (HO^- • 4294967295O) + O = HO^-

(CAS Reg. No. 661-20-1 • 4294967295) +  = CAS Reg. No. 661-20-1

By formula: (CAS Reg. No. 661-20-1 • 4294967295O) + O = CAS Reg. No. 661-20-1

( • 4294967295) +  =

By formula: (O₂^- • 4294967295O) + O = O₂^-

(CAS Reg. No. 13981-20-9 • 4294967295) +  = CAS Reg. No. 13981-20-9

By formula: (CAS Reg. No. 13981-20-9 • 4294967295O) + O = CAS Reg. No. 13981-20-9

(CAS Reg. No. 14380-61-1 • 4294967295) +  = CAS Reg. No. 14380-61-1

By formula: (CAS Reg. No. 14380-61-1 • 4294967295O) + O = CAS Reg. No. 14380-61-1

(CAS Reg. No. 12763-66-5 • 4294967295) +  = CAS Reg. No. 12763-66-5

By formula: (CAS Reg. No. 12763-66-5 • 4294967295O) + O = CAS Reg. No. 12763-66-5

(CAS Reg. No. 14380-62-2 • 4294967295) +  = CAS Reg. No. 14380-62-2

By formula: (CAS Reg. No. 14380-62-2 • 4294967295O) + O = CAS Reg. No. 14380-62-2

(CAS Reg. No. 15065-65-3 • 4294967295) +  = CAS Reg. No. 15065-65-3

By formula: (CAS Reg. No. 15065-65-3 • 4294967295O) + O = CAS Reg. No. 15065-65-3

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, References, Notes

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:
B - John E. Bartmess
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

View reactions leading to O⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

Anion protonation reactions

O^- +  =

By formula: O^- + H⁺ = HO

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, 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.

Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

Smith, Kim, et al., 1997
Smith, J.R.; Kim, J.B.; Lineberger, W.C., High-resolution Threshold Photodetachment Spectroscopy of OH-, Phys. Rev. A, 1997, 55, 3, 2036, https://doi.org/10.1103/PhysRevA.55.2036 . [all data]

Schulz, Mead, et al., 1982
Schulz, P.A.; Mead, R.D.; Jones, P.L.; Lineberger, W.C., OH- and OD- threshold photodetachment, J. Chem. Phys., 1982, 77, 1153. [all data]

Bradforth, Kim, et al., 1993
Bradforth, S.E.; Kim, E.H.; Arnold, D.W.; Neumark, D.M., Photoelectron Spectroscopy of CN-, NCO-, and NCS-, J. Chem. Phys., 1993, 98, 2, 800, https://doi.org/10.1063/1.464244 . [all data]

Wight and Beauchamp, 1980
Wight, C.A.; Beauchamp, J.L., Acidity, basicity, and ion/molecule reactions of isocyanic acid in the gas phase by ICR spectroscopy, J. Phys. Chem., 1980, 84, 2503. [all data]

Ervin, Anusiewicz, et al., 2003
Ervin, K.M.; Anusiewicz, W.; Skurski, P.; Simons, J.; Lineberger, W.C., The only stable state of O-2(-) is the X (2)Pi(g) ground state and it (still!) has an adiabatic electron detachment energy of, J. Phys. Chem. A, 2003, 107, 41, 8521-8529, https://doi.org/10.1021/jp0357323 . [all data]

Travers, Cowles, et al., 1989
Travers, M.J.; Cowles, D.C.; Ellison, G.B., Reinvestigation of the Electron Affinities of O2 and NO, Chem. Phys. Lett., 1989, 164, 5, 449, https://doi.org/10.1016/0009-2614(89)85237-6 . [all data]

Bell, Zemski, et al., 2001
Bell, R.C.; Zemski, K.A.; Justes, D.R.; Castleman, A.W., Formation, structure and bond dissociation thresholds of gas- phase vanadium oxide cluster ions, J. Chem. Phys., 2001, 114, 2, 798-811, https://doi.org/10.1063/1.1329643 . [all data]

Distelrath and Boesl, 2000
Distelrath, V.; Boesl, U., Mass selective gas phase study of ClO, OClO, ClOO and ClAr by anion-ZEKE-photoelectron spectroscopy, Faraday Disc. Chem. Soc., 2000, 115, 161-174, https://doi.org/10.1039/a909618c . [all data]

Gilles, Polak, et al., 1992
Gilles, M.K.; Polak, M.L.; Lineberger, W.C., Photoelectron Spectroscopy of the Halogen Oxide Anions FO-, ClO-, BrO-, IO-, OClO-, and OIO-, J. Chem. Phys., 1992, 96, 11, 8012, https://doi.org/10.1063/1.462352 . [all data]

Gilles, Polak, et al., 1991
Gilles, M.K.; Polak, M.L.; Lineberger, W.C., Photoelectron Spectroscopy of IO-, J. Chem. Phys., 1991, 95, 6, 4723, https://doi.org/10.1063/1.461746 . [all data]

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]

Joiner, Mohr, et al., 2011
Joiner, A.; Mohr, R.H.; Yukich, J.N., High-resolution photodetachment spectroscopy from the lowest threshold of O-, Phys. Rev. A, 2011, 83, 3, 035401, https://doi.org/10.1103/PhysRevA.83.035401 . [all data]

Cavanagh, Gibson, et al., 2007
Cavanagh, S.J.; Gibson, S.T.; Gale, M.N.; Dedman, C.J.; Roberts, E.H.; Lewis, B.R., High-resolution velocity-map-imaging photoelectron spectroscopy of the O- photodetachment fine-structure transitions, Phys. Rev. A, 2007, 76, 5, 052708, https://doi.org/10.1103/PhysRevA.76.052708 . [all data]

Blondel, Chaibi, et al., 2005
Blondel, C.; Chaibi, W.; Delsart, C.; Drag, C.; Goldfarb, F.; Kroger, S., The electron affinities of O, Si, and S revisited with the photodetachment microscope, Eur. Phys. J. D, 2005, 33, 3, 335-342, https://doi.org/10.1140/epjd/e2005-00069-9 . [all data]

Blondel, Delsart, et al., 2001
Blondel, C.; Delsart, C.; Goldfarb, F., Electron spectrometry at the mu eV level and the electron affinities of Si and F, J. Phys. B: Atom. Mol. Opt. Phys., 2001, 34, 9, L281-L288, https://doi.org/10.1088/0953-4075/34/9/101 . [all data]

Neumark, Lykke, et al., 1985
Neumark, D.M.; Lykke, K.R.; Andersen, T.; Lineberger, W.C., Laser photodetachment measurement of the electron affinity of atomic oxygen, Phys. Rev. A:, 1985, 32, 1890. [all data]

Valli, Blondel, et al., 1999
Valli, C.; Blondel, C.; Delsart, C., Measuring electron affinities with the photodetachment microscope, Phys. Rev. A, 1999, 59, 5, 3809-3815, https://doi.org/10.1103/PhysRevA.59.3809 . [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]

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

Banon, Chatillon, et al., 1982
Banon, S.; Chatillon, C.; Allibert, M., High temperature mass spectrometric study of ionization and fragmentation of TiO and TiO₂ gas under electron impact, High Temp. Sci., 1982, 15, 17. [all data]

Radler and Berkowitz, 1977
Radler, K.; Berkowitz, J., Photoionization mass spectrometric study of CSe₂, J. Chem. Phys., 1977, 66, 2176. [all data]

Paule, 1976
Paule, R.C., Mass spectrometric studies of Al₂O₃ vaporization processes, High Temp. Sci., 1976, 8, 257. [all data]

Hildenbrand, 1975
Hildenbrand, D.L., Vertical ionization potential of the CF₂ radical, Chem. Phys. Lett., 1975, 32, 30. [all data]

Cermak, 1975
Cermak, V., Electron spectroscopy of autoionizing states of oxygen, chlorine and bromine atoms, J. Electron Spectrosc. Relat. Phenom., 1975, 6, 135. [all data]

Moore, 1970
Moore, C.E., Ionization potentials and ionization limits derived from the analyses of optical spectra, Natl. Stand. Ref. Data Ser., (U.S. Natl. Bur. Stand.), 1970, 34, 1. [all data]

Jonathan, Morris, et al., 1970
Jonathan, N.; Morris, A.; Smith, D.J.; Ross, K.J., Photoelectron spectra of ground state atomic hydrogen, nitrogen and oxygen, Chem. Phys. Lett., 1970, 7, 497. [all data]

Notes

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

• Symbols used in this document:
  

  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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