Hydronium cation

• Formula: H₃O⁺
• Molecular weight: 19.0227
• IUPAC Standard InChI: InChI=1S/H2O/h1H2/p+1 Copy

  
• IUPAC Standard InChIKey: XLYOFNOQVPJJNP-UHFFFAOYSA-O Copy
• CAS Registry Number: 13968-08-6
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Species with the same structure:
  • Hydroxyl cation
• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data (reactions 1 to 50)
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data: reactions 51 to 51
  • Ion clustering data
  • Vibrational and/or electronic energy levels
• Data at other public NIST sites:
  • Electron-Impact Ionization Cross Sections (on physics web site)
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Gas phase thermochemistry data

Go To: Top, 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.

Reaction thermochemistry data

Go To: Top, Gas phase 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 compiled by: Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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.

Reactions 1 to 50

( • 2) +  = ( • 3)

By formula: (H₃O⁺ • 2H₂O) + H₂O = (H₃O⁺ • 3H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Free energy of reaction

 +  = ( • )

By formula: H₃O⁺ + H₂O = (H₃O⁺ • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Free energy of reaction

( • ) +  = ( • 2)

By formula: (H₃O⁺ • H₂O) + H₂O = (H₃O⁺ • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Free energy of reaction

( • 3) +  = ( • 4)

By formula: (H₃O⁺ • 3H₂O) + H₂O = (H₃O⁺ • 4H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Free energy of reaction

( • 4) +  = ( • 5)

By formula: (H₃O⁺ • 4H₂O) + H₂O = (H₃O⁺ • 5H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Free energy of reaction

( • 5) +  = ( • 6)

By formula: (H₃O⁺ • 5H₂O) + H₂O = (H₃O⁺ • 6H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 6) +  = ( • 7)

By formula: (H₃O⁺ • 6H₂O) + H₂O = (H₃O⁺ • 7H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

 +  = ( • )

By formula: H₃O⁺ + CO₂ = (H₃O⁺ • CO₂)

( • 12) +  = ( • 13)

By formula: (H₃O⁺ • 12H₂O) + H₂O = (H₃O⁺ • 13H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 13) +  = ( • 14)

By formula: (H₃O⁺ • 13H₂O) + H₂O = (H₃O⁺ • 14H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 14) +  = ( • 15)

By formula: (H₃O⁺ • 14H₂O) + H₂O = (H₃O⁺ • 15H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 15) +  = ( • 16)

By formula: (H₃O⁺ • 15H₂O) + H₂O = (H₃O⁺ • 16H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 16) +  = ( • 17)

By formula: (H₃O⁺ • 16H₂O) + H₂O = (H₃O⁺ • 17H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 17) +  = ( • 18)

By formula: (H₃O⁺ • 17H₂O) + H₂O = (H₃O⁺ • 18H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 18) +  = ( • 19)

By formula: (H₃O⁺ • 18H₂O) + H₂O = (H₃O⁺ • 19H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 19) +  = ( • 20)

By formula: (H₃O⁺ • 19H₂O) + H₂O = (H₃O⁺ • 20H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 20) +  = ( • 21)

By formula: (H₃O⁺ • 20H₂O) + H₂O = (H₃O⁺ • 21H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 21) +  = ( • 22)

By formula: (H₃O⁺ • 21H₂O) + H₂O = (H₃O⁺ • 22H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 22) +  = ( • 23)

By formula: (H₃O⁺ • 22H₂O) + H₂O = (H₃O⁺ • 23H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 23) +  = ( • 24)

By formula: (H₃O⁺ • 23H₂O) + H₂O = (H₃O⁺ • 24H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 24) +  = ( • 25)

By formula: (H₃O⁺ • 24H₂O) + H₂O = (H₃O⁺ • 25H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 10) +  = ( • 11)

By formula: (H₃O⁺ • 10H₂O) + H₂O = (H₃O⁺ • 11H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 11) +  = ( • 12)

By formula: (H₃O⁺ • 11H₂O) + H₂O = (H₃O⁺ • 12H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 25) +  = ( • 26)

By formula: (H₃O⁺ • 25H₂O) + H₂O = (H₃O⁺ • 26H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 26) +  = ( • 27)

By formula: (H₃O⁺ • 26H₂O) + H₂O = (H₃O⁺ • 27H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 9) +  = ( • 10)

By formula: (H₃O⁺ • 9H₂O) + H₂O = (H₃O⁺ • 10H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 8) +  = ( • 9)

By formula: (H₃O⁺ • 8H₂O) + H₂O = (H₃O⁺ • 9H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 7) +  = ( • 8)

By formula: (H₃O⁺ • 7H₂O) + H₂O = (H₃O⁺ • 8H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • 2 • 3) +  = ( • 3 • 3)

By formula: (H₃O⁺ • 2N₂ • 3H₂O) + N₂ = (H₃O⁺ • 3N₂ • 3H₂O)

( • 3) +  = ( • 4)

By formula: (H₃O⁺ • 3N₂O) + N₂O = (H₃O⁺ • 4N₂O)

( • 3 • 2) +  = ( • 4 • 2)

By formula: (H₃O⁺ • 3N₂ • 2H₂O) + N₂ = (H₃O⁺ • 4N₂ • 2H₂O)

( • 27) +  = ( • 28)

By formula: (H₃O⁺ • 27H₂O) + H₂O = (H₃O⁺ • 28H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

( • ) +  = ( • 2)

By formula: (H₃O⁺ • CH₄) + CH₄ = (H₃O⁺ • 2CH₄)

( • 4) +  = ( •  • 4)

By formula: (H₃O⁺ • 4H₂O) + O₂S = (H₃O⁺ • O₂S • 4H₂O)

Free energy of reaction

( • 2 • 2) +  = ( • 3 • 2)

By formula: (H₃O⁺ • 2N₂ • 2H₂O) + N₂ = (H₃O⁺ • 3N₂ • 2H₂O)

( • 2) +  = ( •  • 2)

By formula: (H₃O⁺ • 2H₂O) + CHN = (H₃O⁺ • CHN • 2H₂O)

( • 2 • ) +  = ( • 3 • )

By formula: (H₃O⁺ • 2N₂ • H₂O) + N₂ = (H₃O⁺ • 3N₂ • H₂O)

( •  • 2) +  = ( • 2 • 2)

By formula: (H₃O⁺ • N₂ • 2H₂O) + N₂ = (H₃O⁺ • 2N₂ • 2H₂O)

( •  • 3) +  = ( • 2 • 3)

By formula: (H₃O⁺ • N₂ • 3H₂O) + N₂ = (H₃O⁺ • 2N₂ • 3H₂O)

( •  • ) +  = ( • 2 • )

By formula: (H₃O⁺ • N₂ • H₂O) + N₂ = (H₃O⁺ • 2N₂ • H₂O)

( • 2) +  = ( • 3)

By formula: (H₃O⁺ • 2N₂O) + N₂O = (H₃O⁺ • 3N₂O)

( • 2) +  = ( •  • 2)

By formula: (H₃O⁺ • 2H₂O) + N₂ = (H₃O⁺ • N₂ • 2H₂O)

( • ) +  = ( • 2)

By formula: (H₃O⁺ • N₂O) + N₂O = (H₃O⁺ • 2N₂O)

( • ) +  = ( •  • )

By formula: (H₃O⁺ • H₂O) + N₂ = (H₃O⁺ • N₂ • H₂O)

( • 2) +  = ( • 3)

By formula: (H₃O⁺ • 2CO₂) + CO₂ = (H₃O⁺ • 3CO₂)

( • ) +  = ( • 2)

By formula: (H₃O⁺ • CO₂) + CO₂ = (H₃O⁺ • 2CO₂)

 +  = ( • )

By formula: H₃O⁺ + N₂O = (H₃O⁺ • N₂O)

 +  = ( • )

By formula: H₃O⁺ + O₂S = (H₃O⁺ • O₂S)

 +  = ( • )

By formula: H₃O⁺ + CH₄ = (H₃O⁺ • CH₄)

( • 3) +  = ( •  • 3)

By formula: (H₃O⁺ • 3H₂O) + O₂S = (H₃O⁺ • O₂S • 3H₂O)

Free energy of reaction

References

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

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

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Bierbaum, Golde, et al., 1976
Bierbaum, V.M.; Golde, M.F.; Kaufman, F., Flowing Afterglow Studies of Hydronium Ion Clustering Including Diffusion Effects, J. Chem. Phys., 1976, 65, 7, 2715, https://doi.org/10.1063/1.433415 . [all data]

Arifov, Pozharov, et al., 1971
Arifov, U.A.; Pozharov, S.L.; Chernov, I.G., High Energy Chem., 1971, 5, 1. [all data]

Puckett and Teague, 1971
Puckett, L.J.; Teague, A.W., Production of H3O+.nH2O from NO+ Precursor in NO - H2O Gas Mixtures, J. Chem. Phys., 1971, 54, 6, 2564, https://doi.org/10.1063/1.1675213 . [all data]

Good, Durden, et al., 1970
Good, A.; Durden, D.A.; Kebarle, P., Ion-Molecule Reactions in Pure Nitrogen and Nitrogen Containing Traces of Water at Total Pressures 0.5 - 4 torr. Kinetics of Clustering Reactions Forming H+(H2O)n, J. Chem. Phys., 1970, 52, 1, 212, https://doi.org/10.1063/1.1672667 . [all data]

Good, Durden, et al., 1970, 2
Good, A.; Durden, D.A.; Kebarle, P., Mechanism and Rate Constants of Ion-Molecule Reactions Leading to Formation of H+(H2O)n in Moist Oxygen and Air, J. Chem. Phys., 1970, 52, 1, 222, https://doi.org/10.1063/1.1672668 . [all data]

Klassen, Blades, et al., 1995
Klassen, J.S.; Blades, A.T.; Kebarle, P., Determinations of Ion-Molecule Equilibria Involving Ions Produced by Electrospray. Hydration of Protonated Amines, Diamines, and Some Small Peptides, J. Phys. Chem., 1995, 99, 42, 15509, https://doi.org/10.1021/j100042a027 . [all data]

Lau, Ikuta, et al., 1982
Lau, Y.K.; Ikuta, S.; Kebarle, P., Thermodynamics and Kinetics of the Gas - Phase Reactions: H3O+(H2O)n - 1 + H2O = H3O+(H2O)n, J. Am. Chem. Soc., 1982, 104, 6, 1462, https://doi.org/10.1021/ja00370a002 . [all data]

Kebarle, Searles, et al., 1967
Kebarle, P.; Searles, S.K.; Zolla, A.; Scarborough, J.; Arshadi, M., The Solvation of the Hydrogen Ion by Water Molecules in the Gas Phase. Heats and Entropies of Solvation of the Individual Reactions: H+(H2O)n-1 + H2O = H+(H2O)n, J. Am. Chem. Soc., 1967, 89, 25, 6393, https://doi.org/10.1021/ja01001a001 . [all data]

Shi, Ford, et al., 1993
Shi, Z.; Ford, V.; Wei, S.; Castleman, A.W., Water Clusters - Contributions of Binding Energy and Entropy to Stability, J. Chem. Phys., 1993, 99, 10, 8009, https://doi.org/10.1063/1.465678 . [all data]

Magnera, David, et al., 1991
Magnera, T.F.; David, D.E.; Michl, J., The First Twenty - Eight Proton Hydration Energies, Chem. Phys. Lett., 1991, 182, 3-4, 363, https://doi.org/10.1016/0009-2614(91)80230-U . [all data]

Szulejko and McMahon, 1992
Szulejko, J.; McMahon, T.B., personal communication, 1992. [all data]

Hiraoka, Shoda, et al., 1986
Hiraoka, K.; Shoda, T.; Morise, K.; Yamabe, S.; Kawai, E.; Hirao, K., Stability and structure of cluster ions in the gas phase: Carbon dioxide with Cl^-, H₃O⁺, HCO₂⁺ and HCO⁺, J. Chem. Phys., 1986, 84, 2091. [all data]

Meot-Ner (Mautner) and Field, 1977
Meot-Ner (Mautner), M.; Field, F.H., Proton Affinity and Ion - Molecule Clustering in CO2 and CS2. Applications in Martian Ionospheric Chemistry, J. Chem. Phys., 1977, 66, 10, 4527, https://doi.org/10.1063/1.433706 . [all data]

Gheno and Fitaire, 1987
Gheno, F.; Fitaire, M., Association of N2 with NH4+ and H3O+(H2O)n, n = 1,2,3, J. Chem. Phys., 1987, 87, 2, 953, https://doi.org/10.1063/1.453250 . [all data]

Hiraoka, Fujimaki, et al., 1994
Hiraoka, K.; Fujimaki, S.; Aruga, K.; Sato, T.; Yamabe, S., Gas-Phase Solavtion of NO+, O2+, N2O+, and H3O+ with N2O, J. Chem. Phys., 1994, 101, 5, 4073, https://doi.org/10.1063/1.467524 . [all data]

Bennet and Field, 1972
Bennet, S.L.; Field, F.H., Reversible Reactions of Gaseous Ions. V. The Methane - Water System at Low Temperatures, J. Am. Chem. Soc., 1972, 94, 15, 5188, https://doi.org/10.1021/ja00770a008 . [all data]

Banic and Iribarne, 1985
Banic, C.M.; Iribarne, J.V., Equilibrium Constants for Clustering of Neutral Molecules about Gaseous Ions, J. Chem. Phys., 1985, 83, 12, 6432, https://doi.org/10.1063/1.449543 . [all data]

Meot-Ner (Mautner) and Speller, 1989
Meot-Ner (Mautner), M.; Speller, C.V., Multicomponent Cluster Ions.3. Comparative Stabilities of Cationic and Anionic Hydrogen Bonded Networks. Mixed Clusters of Water and Hydrogen Cyanide, J. Phys. Chem., 1989, 93, 6580. [all data]

Notes

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

• Symbols used in this document:
  

  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  T	Temperature
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

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