Methane

• Formula: CH₄
• Molecular weight: 16.0425
• IUPAC Standard InChI: InChI=1S/CH4/h1H4 Copy

  
• IUPAC Standard InChIKey: VNWKTOKETHGBQD-UHFFFAOYSA-N Copy
• CAS Registry Number: 74-82-8
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: Marsh gas; Methyl hydride; CH4; Fire Damp; R 50; Biogas; R 50 (refrigerant)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Ion clustering 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 112
  • Henry's Law data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Vibrational and/or electronic energy levels
  • Fluid Properties
• Data at other public NIST sites:
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  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Gas Phase Kinetics Database
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Ion clustering data

Go To: Top, 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

 +  = CH₄Br^-

By formula: Br^- + CH₄ = CH₄Br^-

 +  = ( • )

By formula: CF₃⁺ + CH₄ = (CF₃⁺ • CH₄)

CH₄Cl^- + 2 = C₂H₈Cl^-

By formula: CH₄Cl^- + 2CH₄ = C₂H₈Cl^-

CH₄F^- + 2 = C₂H₈F^-

By formula: CH₄F^- + 2CH₄ = C₂H₈F^-

CH₅⁺ +  = (CH₅⁺ • )

By formula: CH₅⁺ + CH₄ = (CH₅⁺ • CH₄)

(CH₅⁺ • ) +  = (CH₅⁺ • 2)

By formula: (CH₅⁺ • CH₄) + CH₄ = (CH₅⁺ • 2CH₄)

(CH₅⁺ • 2) +  = (CH₅⁺ • 3)

By formula: (CH₅⁺ • 2CH₄) + CH₄ = (CH₅⁺ • 3CH₄)

(CH₅⁺ • 3) +  = (CH₅⁺ • 4)

By formula: (CH₅⁺ • 3CH₄) + CH₄ = (CH₅⁺ • 4CH₄)

(CH₅⁺ • 4) +  = (CH₅⁺ • 5)

By formula: (CH₅⁺ • 4CH₄) + CH₄ = (CH₅⁺ • 5CH₄)

(CH₅⁺ • 5) +  = (CH₅⁺ • 6)

By formula: (CH₅⁺ • 5CH₄) + CH₄ = (CH₅⁺ • 6CH₄)

(CH₅⁺ • 6) +  = (CH₅⁺ • 7)

By formula: (CH₅⁺ • 6CH₄) + CH₄ = (CH₅⁺ • 7CH₄)

(CH₅⁺ • 7) +  = (CH₅⁺ • 8)

By formula: (CH₅⁺ • 7CH₄) + CH₄ = (CH₅⁺ • 8CH₄)

(CH₅⁺ • 8) +  = (CH₅⁺ • 9)

By formula: (CH₅⁺ • 8CH₄) + CH₄ = (CH₅⁺ • 9CH₄)

C₂H₅⁺ +  = (C₂H₅⁺ • )

By formula: C₂H₅⁺ + CH₄ = (C₂H₅⁺ • CH₄)

(C₂H₅⁺ • ) +  = (C₂H₅⁺ • 2)

By formula: (C₂H₅⁺ • CH₄) + CH₄ = (C₂H₅⁺ • 2CH₄)

(C₂H₅⁺ • 2) +  = (C₂H₅⁺ • 3)

By formula: (C₂H₅⁺ • 2CH₄) + CH₄ = (C₂H₅⁺ • 3CH₄)

(C₂H₅⁺ • 3) +  = (C₂H₅⁺ • 4)

By formula: (C₂H₅⁺ • 3CH₄) + CH₄ = (C₂H₅⁺ • 4CH₄)

(C₂H₅⁺ • 4) +  = (C₂H₅⁺ • 5)

By formula: (C₂H₅⁺ • 4CH₄) + CH₄ = (C₂H₅⁺ • 5CH₄)

(C₂H₅⁺ • 5) +  = (C₂H₅⁺ • 6)

By formula: (C₂H₅⁺ • 5CH₄) + CH₄ = (C₂H₅⁺ • 6CH₄)

(C₂H₅⁺ • 6) +  = (C₂H₅⁺ • 7)

By formula: (C₂H₅⁺ • 6CH₄) + CH₄ = (C₂H₅⁺ • 7CH₄)

(C₂H₅⁺ • 7) +  = (C₂H₅⁺ • 8)

By formula: (C₂H₅⁺ • 7CH₄) + CH₄ = (C₂H₅⁺ • 8CH₄)

(C₂H₅⁺ • 8) +  = (C₂H₅⁺ • 9)

By formula: (C₂H₅⁺ • 8CH₄) + CH₄ = (C₂H₅⁺ • 9CH₄)

(C₂H₅⁺ • 9) +  = (C₂H₅⁺ • 10)

By formula: (C₂H₅⁺ • 9CH₄) + CH₄ = (C₂H₅⁺ • 10CH₄)

C₂H₈F^- + 3 = C₃H₁₂F^-

By formula: C₂H₈F^- + 3CH₄ = C₃H₁₂F^-

C₃H₇⁺ +  = (C₃H₇⁺ • )

By formula: C₃H₇⁺ + CH₄ = (C₃H₇⁺ • CH₄)

(C₃H₇⁺ • ) +  = (C₃H₇⁺ • 2)

By formula: (C₃H₇⁺ • CH₄) + CH₄ = (C₃H₇⁺ • 2CH₄)

(C₃H₇⁺ • 2) +  = (C₃H₇⁺ • 3)

By formula: (C₃H₇⁺ • 2CH₄) + CH₄ = (C₃H₇⁺ • 3CH₄)

(C₃H₇⁺ • 3) +  = (C₃H₇⁺ • 4)

By formula: (C₃H₇⁺ • 3CH₄) + CH₄ = (C₃H₇⁺ • 4CH₄)

(C₃H₇⁺ • 4) +  = (C₃H₇⁺ • 5)

By formula: (C₃H₇⁺ • 4CH₄) + CH₄ = (C₃H₇⁺ • 5CH₄)

(C₃H₇⁺ • 5) +  = (C₃H₇⁺ • 6)

By formula: (C₃H₇⁺ • 5CH₄) + CH₄ = (C₃H₇⁺ • 6CH₄)

(C₃H₇⁺ • 6) +  = (C₃H₇⁺ • 7)

By formula: (C₃H₇⁺ • 6CH₄) + CH₄ = (C₃H₇⁺ • 7CH₄)

(C₃H₇⁺ • 7) +  = (C₃H₇⁺ • 8)

By formula: (C₃H₇⁺ • 7CH₄) + CH₄ = (C₃H₇⁺ • 8CH₄)

C₃H₁₂F^- + 4 = C₄H₁₆F^-

By formula: C₃H₁₂F^- + 4CH₄ = C₄H₁₆F^-

C₄H₉⁺ +  = (C₄H₉⁺ • )

By formula: C₄H₉⁺ + CH₄ = (C₄H₉⁺ • CH₄)

(C₄H₉⁺ • ) +  = (C₄H₉⁺ • 2)

By formula: (C₄H₉⁺ • CH₄) + CH₄ = (C₄H₉⁺ • 2CH₄)

(C₄H₉⁺ • 2) +  = (C₄H₉⁺ • 3)

By formula: (C₄H₉⁺ • 2CH₄) + CH₄ = (C₄H₉⁺ • 3CH₄)

(C₄H₉⁺ • 3) +  = (C₄H₉⁺ • 4)

By formula: (C₄H₉⁺ • 3CH₄) + CH₄ = (C₄H₉⁺ • 4CH₄)

(C₄H₉⁺ • 4) +  = (C₄H₉⁺ • 5)

By formula: (C₄H₉⁺ • 4CH₄) + CH₄ = (C₄H₉⁺ • 5CH₄)

(C₄H₉⁺ • 5) +  = (C₄H₉⁺ • 6)

By formula: (C₄H₉⁺ • 5CH₄) + CH₄ = (C₄H₉⁺ • 6CH₄)

(C₄H₉⁺ • 6) +  = (C₄H₉⁺ • 7)

By formula: (C₄H₉⁺ • 6CH₄) + CH₄ = (C₄H₉⁺ • 7CH₄)

(C₄H₉⁺ • 7) +  = (C₄H₉⁺ • 8)

By formula: (C₄H₉⁺ • 7CH₄) + CH₄ = (C₄H₉⁺ • 8CH₄)

(C₄H₉⁺ • 8) +  = (C₄H₉⁺ • 9)

By formula: (C₄H₉⁺ • 8CH₄) + CH₄ = (C₄H₉⁺ • 9CH₄)

C₄H₁₆F^- + 5 = C₅H₂₀F^-

By formula: C₄H₁₆F^- + 5CH₄ = C₅H₂₀F^-

C₅H₂₀F^- + 6 = C₆H₂₄F^-

By formula: C₅H₂₀F^- + 6CH₄ = C₆H₂₄F^-

C₅MnO₅⁺ +  = (C₅MnO₅⁺ • )

By formula: C₅MnO₅⁺ + CH₄ = (C₅MnO₅⁺ • CH₄)

C₆H₂₄F^- + 7 = C₇H₂₈F^-

By formula: C₆H₂₄F^- + 7CH₄ = C₇H₂₈F^-

C₇H₂₈F^- + 8 = C₈H₃₂F^-

By formula: C₇H₂₈F^- + 8CH₄ = C₈H₃₂F^-

C₈H₃₂F^- + 9 = C₉H₃₆F^-

By formula: C₈H₃₂F^- + 9CH₄ = C₉H₃₆F^-

C₉H₃₆F^- + 10 = C₁₀H₄₀F^-

By formula: C₉H₃₆F^- + 10CH₄ = C₁₀H₄₀F^-

 +  = CH₄Cl^-

By formula: Cl^- + CH₄ = CH₄Cl^-

 +  = ( • )

By formula: Co⁺ + CH₄ = (Co⁺ • CH₄)

Enthalpy of reaction

( • ) +  = ( • 2)

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

Enthalpy of reaction

( • 2) +  = ( • 3)

By formula: (Co⁺ • 2CH₄) + CH₄ = (Co⁺ • 3CH₄)

Enthalpy of reaction

Free energy of reaction

( • 3) +  = ( • 4)

By formula: (Co⁺ • 3CH₄) + CH₄ = (Co⁺ • 4CH₄)

Enthalpy of reaction

( • ) +  = ( •  • )

By formula: (Co⁺ • C₂H₆) + CH₄ = (Co⁺ • CH₄ • C₂H₆)

Enthalpy of reaction

( • ) +  = ( •  • )

By formula: (Co⁺ • H₂O) + CH₄ = (Co⁺ • CH₄ • H₂O)

Enthalpy of reaction

( • ) +  = ( •  • )

By formula: (Co⁺ • H₂) + CH₄ = (Co⁺ • CH₄ • H₂)

Enthalpy of reaction

 +  = CH₄F^-

By formula: F^- + CH₄ = CH₄F^-

 +  = ( • )

By formula: Fe⁺ + CH₄ = (Fe⁺ • CH₄)

Enthalpy of reaction

( • ) +  = ( • 2)

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

Enthalpy of reaction

( • 2) +  = ( • 3)

By formula: (Fe⁺ • 2CH₄) + CH₄ = (Fe⁺ • 3CH₄)

Enthalpy of reaction

( • 3) +  = ( • 4)

By formula: (Fe⁺ • 3CH₄) + CH₄ = (Fe⁺ • 4CH₄)

Enthalpy of reaction

 +  = ( • )

By formula: H₃O⁺ + CH₄ = (H₃O⁺ • CH₄)

( • ) +  = ( • 2)

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

H₃S⁺ +  = (H₃S⁺ • )

By formula: H₃S⁺ + CH₄ = (H₃S⁺ • CH₄)

 +  = ( • )

By formula: H₄N⁺ + CH₄ = (H₄N⁺ • CH₄)

 +  = CH₄I^-

By formula: I^- + CH₄ = CH₄I^-

 +  = ( • )

By formula: Mg⁺ + CH₄ = (Mg⁺ • CH₄)

( • ) +  = ( • 2)

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

 +  = ( • )

By formula: Na⁺ + CH₄ = (Na⁺ • CH₄)

References

Go To: Top, Ion clustering data, Notes

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

Hiraoka, Mizuno, et al., 2001
Hiraoka, K.; Mizuno, T.; Iino, T.; Eguchi, D.; Yamabe, S., Characteristic changes of bond energies for gas-phase cluster ions of halide ions with methane and chloromethanes, J. Phys. Chem. A, 2001, 105, 20, 4887-4893, https://doi.org/10.1021/jp010143n . [all data]

Bennet and Field, 1972
Bennet, S.L.; Field, F.H., Reversible Reactions of Gaseous Ions. VI. The NH3 - CH4, H2S - CH4 and CF4 - CH4 Systems at Low Temperatures, J. Am. Chem. Soc., 1972, 94, 18, 6305, https://doi.org/10.1021/ja00773a009 . [all data]

Hiraoka and Mori, 1989
Hiraoka, K.; Mori, T., Gas - Phase Stability and Structure of Cluster Ions CH5+(CH4)n with n = 1 - 9, Chem. Phys. Lett., 1989, 161, 2, 111, https://doi.org/10.1016/0009-2614(89)85040-7 . [all data]

Hiraoka and Kebarle, 1975
Hiraoka, K.; Kebarle, P., Energetics, Stabilities and Possible Structures of CH5+(CH4)n Clusters from Gas Phase Study of Equilibria CH5+(CH4)n - 1 + CH4 = CH5+(CH4)n for n = 1 - 5, J. Am. Chem. Soc., 1975, 97, 15, 4179, https://doi.org/10.1021/ja00848a005 . [all data]

Field and Beggs, 1971
Field, F.H.; Beggs, D.P., Reversible Reactions of Gas Phase Ions. III. Studies with Methane at 0.1-1.0 Torr and 77-300 K, J. Am. Chem. Soc., 1971, 93, 7, 1585, https://doi.org/10.1021/ja00736a003 . [all data]

Hiraoka, Mori, et al., 1993
Hiraoka, K.; Mori, T.; Yamabe, S., The Gas-Phase Solvation of C2H5+, s-C3H7+ and s-C4H9+ with CH4. The Isomeric Structures of C2H5+ and C2H5+.CH4, Chem. Phys. Lett., 1993, 207, 2-3, 178, https://doi.org/10.1016/0009-2614(93)87011-Q . [all data]

Hiroka and Kebarle, 1975
Hiroka, K.; Kebarle, P., Information on the Proton Affinity and Protolysis of Propane from Measurement of the Ion Cluster Equilibrium: C2H5+ + CH4 = C3H9+, Can. J. Phys., 1975, 53, 970. [all data]

Hiraoka and Kebarle, 1976
Hiraoka, K.; Kebarle, P., Stabilities and Energetics of Pentacoordinated Carbonium Ions. The Isomeric C2H7+ Ions and Some Higher Analogues: C3H9+ and C4H11+, J. Am. Chem. Soc., 1976, 98, 20, 6119, https://doi.org/10.1021/ja00436a009 . [all data]

Hop and McMahon, 1991
Hop, C.E.C.A.; McMahon, T.B., Observation of a Weakly Bound Mn(CO)5+/CH4 Complex, J. Am. Chem. Soc., 1991, 113, 1, 355, https://doi.org/10.1021/ja00001a050 . [all data]

Kemper, Bushnell, et al., 1993
Kemper, P.R.; Bushnell, J.; Von Koppen, P.; Bowers, M.T., Binding Energies of Co+(H2/CH4/C2H6)1,2,3 Clusters, J. Phys. Chem., 1993, 97, 9, 1810, https://doi.org/10.1021/j100111a016 . [all data]

Haynes and Armentrout, 1996
Haynes, C.L.; Armentrout, P.B., Guided Ion Beam Determination of the Co+ - H2 Bond Dissociation energy, Chem Phys. Let., 1996, 249, 1-2, 64, https://doi.org/10.1016/0009-2614(95)01337-7 . [all data]

Armentrout and Kickel, 1994
Armentrout, P.B.; Kickel, B.L., Gas Phase Thermochemistry of Transition Metal Ligand Systems: Reassessment of Values and Periodic Trends, in Organometallic Ion Chemistry, B. S. Freiser, ed, 1994. [all data]

Kemper, Bushnell, et al., 1993, 2
Kemper, P.R.; Bushnell, J.; Von Helden, G.; Bowers, M.T., Co+(H2)n Clusters: Binding Energies and Molecular Parameters, J. Chem Phys., 1993, 97, 1, 52, https://doi.org/10.1021/j100103a012 . [all data]

Bennet and Field, 1972, 2
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]

Andersen, Muntean, et al., 2000
Andersen, A.; Muntean, F.; Walter, D.; Rue, C.; Armentrout, P.B., Collision-Induced Dissociation and Theoretical Studies of Mg+ Complexes with CO, CO2, NH3, CH4, CH3OH, and C6H6, J. Phys. Chem. A, 2000, 104, 4, 692, https://doi.org/10.1021/jp993031t . [all data]

Castleman, Peterson, et al., 1983
Castleman, A.W.; Peterson, K.I.; Upschulte, B.L.; Schelling, F.J., Energetics and Structure of Na+ Cluster Ions, Int. J. Mass Spectrom. Ion Phys., 1983, 47, 203, https://doi.org/10.1016/0020-7381(83)87171-X . [all data]

Notes

Go To: Top, Ion clustering data, References

• Symbols used in this document:
  

  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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