MeO anion

• Formula: CH₃O^-
• Molecular weight: 31.0345
• CAS Registry Number: 3315-60-4
• Information on this page:
  • Gas phase ion energetics data
  • Ion clustering data
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • Vibrational and/or electronic energy levels
• Options:
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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 compiled by: John E. Bartmess

Electron affinity of neutral species

Protonation reactions

CH₃O^- +  =

By formula: CH₃O^- + H⁺ = CH₄O

Ion clustering 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 compiled as indicated in comments:
B - John E. Bartmess
M - 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. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

CH₃O^- +  = (CH₃O^- • )

By formula: CH₃O^- + BF₃ = (CH₃O^- • BF₃)

CH₃O^- +  = C₂H₄D₇O₂^-

By formula: CH₃O^- + CD₄O = C₂H₄D₇O₂^-

CH₃O^- +  = C₂H₄F₃O^-

By formula: CH₃O^- + CHF₃ = C₂H₄F₃O^-

(CH₃O^- • 4294967295) +  = CH₃O^-

By formula: (CH₃O^- • 4294967295CH₂O) + CH₂O = CH₃O^-

CH₃O^- +  = (CH₃O^- • )

By formula: CH₃O^- + CH₄O = (CH₃O^- • CH₄O)

Free energy of reaction

(CH₃O^- • ) +  = (CH₃O^- • 2)

By formula: (CH₃O^- • CH₄O) + CH₄O = (CH₃O^- • 2CH₄O)

(CH₃O^- • 2) +  = (CH₃O^- • 3)

By formula: (CH₃O^- • 2CH₄O) + CH₄O = (CH₃O^- • 3CH₄O)

(CH₃O^- • 3) +  = (CH₃O^- • 4)

By formula: (CH₃O^- • 3CH₄O) + CH₄O = (CH₃O^- • 4CH₄O)

(CH₃O^- • ) +  = (CH₃O^- •  • )

By formula: (CH₃O^- • CH₄O) + H₂O = (CH₃O^- • H₂O • CH₄O)

Bond type: Hydrogen bond (negative ion to hydride)

(CH₃O^- • 2) +  = (CH₃O^- •  • 2)

By formula: (CH₃O^- • 2CH₄O) + H₂O = (CH₃O^- • H₂O • 2CH₄O)

Bond type: Hydrogen bond (negative ion to hydride)

CH₃O^- +  = C₇H₈F₃OSi^-

By formula: CH₃O^- + C₆H₅F₃Si = C₇H₈F₃OSi^-

CH₃O^- +  = (CH₃O^- • )

By formula: CH₃O^- + H₂O = (CH₃O^- • H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

Free energy of reaction

(CH₃O^- • ) +  = (CH₃O^- •  • )

By formula: (CH₃O^- • H₂O) + CH₄O = (CH₃O^- • CH₄O • H₂O)

Free energy of reaction

(CH₃O^- •  • ) +  = (CH₃O^- • 2 • )

By formula: (CH₃O^- • H₂O • CH₄O) + H₂O = (CH₃O^- • 2H₂O • CH₄O)

Bond type: Hydrogen bond (negative ion to hydride)

(CH₃O^- • ) +  = (CH₃O^- • 2)

By formula: (CH₃O^- • H₂O) + H₂O = (CH₃O^- • 2H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

Free energy of reaction

(CH₃O^- • 2) +  = (CH₃O^- • 3)

By formula: (CH₃O^- • 2H₂O) + H₂O = (CH₃O^- • 3H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

Free energy of reaction

(CH₃O^- • 3) +  = (CH₃O^- • 4)

By formula: (CH₃O^- • 3H₂O) + H₂O = (CH₃O^- • 4H₂O)

Bond type: Hydrogen bond (negative ion to hydride)

References

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

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

Nee, Osterwalder, et al., 2006
Nee, M.J.; Osterwalder, A.; Zhou, J.; Neumark, D.M., Slow electron velocity-map imaging photoelectron spectra of the methoxide anion, J. Chem. Phys., 2006, 125, 1, 014306, https://doi.org/10.1063/1.2212411 . [all data]

Ramond, Davico, et al., 2000
Ramond, T.M.; Davico, G.E.; Schwartz, R.L.; Lineberger, W.C., Vibronic structure of alkoxy radicals via photoelectron spectroscopy, J. Chem. Phys., 2000, 112, 3, 1158-1169, https://doi.org/10.1063/1.480767 . [all data]

Osborn, Leahy, et al., 1998
Osborn, D.L.; Leahy, D.J.; Kim, E.H.; deBeer, E.; Neumark, D.M., Photoelectron spectroscopy of CH3O- and CD3O-, Chem. Phys. Lett., 1998, 292, 4-6, 651-655, https://doi.org/10.1016/S0009-2614(98)00717-9 . [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

Engleking, Ellison, et al., 1978
Engleking, P.C.; Ellison, G.B.; Lineberger, W.C., Laser photodetachment electron spectrometry of methoxide, deuteromethoxide, and thiomethoxide: Electron affinities and vibrational structure of CH₃O, and CH₃S, J. Chem. Phys., 1978, 69, 1826. [all data]

Hiraoka, Shimizu, et al., 1995
Hiraoka, K.; Shimizu, A.; Minamitsu, A.; Nasu, M.; Fujimaki, S.; Yamabe, S., The small binding energies of the negative cluster ions: SF5-(SF6)1, SF6-(SF6)1 and F-(SF6)n (n=1 and 2), in the gas phase, Chem. Phys. Lett., 1995, 241, 5-6, 623, https://doi.org/10.1016/0009-2614(95)00676-U . [all data]

Janousek, Zimmerman, et al., 1978
Janousek, B.K.; Zimmerman, A.H.; Reed, K.J.; Brauman, J.I., Electron detachment from aliphatic molecular anions. Gas phase electron affinites of methoxyl, tert-butoxyl, and neopentoxyl radicals, J. Am. Chem. Soc., 1978, 100, 6142. [all data]

Reed and Brauman, 1975
Reed, K.J.; Brauman, J.I., Electron affinities of alkoxy radicals and the bond dissociation energies in aliphatic alcohols, J. Am. Chem. Soc., 1975, 97, 1625. [all data]

Tsuda and Hamill, 1964
Tsuda, S.; Hamill, W.H., Ionization Efficiency Measurements by the Retarding Potential Difference Method, Adv. Mass Spectrom., 1964, 3, 249. [all data]

Page and Goode, 1969
Page, F.M.; Goode, G.C., Negative Ions and the Magnetron., Wiley, NY, 1969. [all data]

Haas and Harrison, 1993
Haas, M.J.; Harrison, A.G., The Fragmentation of Proton-Bound Cluster Ions and the Gas-Phase Acidities of Alcohols, Int. J. Mass Spectrom. Ion Proc., 1993, 124, 2, 115, https://doi.org/10.1016/0168-1176(93)80003-W . [all data]

Meot-ner and Sieck, 1986
Meot-ner, M.; Sieck, L.W., Relative acidities of water and methanol, and the stabilities of the dimer adducts, J. Phys. Chem., 1986, 90, 6687. [all data]

Blair, Isolani, et al., 1973
Blair, L.K.; Isolani, P.C.; Riveros, J.M., Formation, reactivity, and relative stability of clustered alkoxide ions by ICR spectroscopy, J. Am. Chem. Soc., 1973, 95, 1057. [all data]

Chabinyc and Brauman, 2000
Chabinyc, M.L.; Brauman, J.I., Unusual ionic hydrogen bonds: Complexes of acetylides and fluoroform, J. Am. Chem. Soc., 2000, 122, 36, 8739-8745, https://doi.org/10.1021/ja000806z . [all data]

Chabinyc and Brauman, 1998
Chabinyc, M.L.; Brauman, J.I., Acidity, basicity, and the stability of hydrogen bonds: Complexes of RO-+HCF3, J. Am. Chem. Soc., 1998, 120, 42, 10863-10870, https://doi.org/10.1021/ja9817592 . [all data]

Paul and Kebarle, 1990
Paul, G.J.C.; Kebarle, P., Thermodynamics of the Association Reactions OH- - H2O = HOHOH- and CH3O- - CH3OH = CH3OHOCH3- in the Gas Phase, J. Phys. Chem., 1990, 94, 12, 5184, https://doi.org/10.1021/j100375a076 . [all data]

Caldwell, Rozeboom, et al., 1984
Caldwell, G.; Rozeboom, M.D.; Kiplinger, J.P.; Bartmess, J.E., Anion-alcohol hydrogen bond strengths in the gas phase, J. Am. Chem. Soc., 1984, 106, 4660. [all data]

Moylan, Dodd, et al., 1985
Moylan, C.R.; Dodd, J.A.; Brauman, J.I., Electron photodetachment spectroscopy of Sslvated anions. A probe of structure and energetics, Chem. Phys. Lett., 1985, 118, 38. [all data]

Meot-Ner(Mautner), 1986
Meot-Ner(Mautner), M., Comparative Stabilities of Cationic and Anionic Hydrogen-Bonded Networks. Mixed Clusters of Water-Methanol, J. Am. Chem. Soc., 1986, 108, 20, 6189, https://doi.org/10.1021/ja00280a014 . [all data]

Mustanir, Matsuoka, et al., 2006
Mustanir; Matsuoka, M.; Mishima, M.; Koch, H., Stability of complexes of phenylacetylides and benzyl alkoxides with methanol in the gas phase. Acid-base correlation in the ionic hydrogen-bond strength, Bull. Chem. Soc. Japan, 2006, 79, 7, 1118-1125, https://doi.org/10.1246/bcsj.79.1118 . [all data]

MacKay and Bohme, 1978
MacKay, G.I.; Bohme, D.K., Proton-Transfer Reactions in Nitromethane at 297K, Int. J. Mass Spectrom. Ion Phys., 1978, 26, 4, 327, https://doi.org/10.1016/0020-7381(78)80052-7 . [all data]

Krouse, Lardin, et al., 2003
Krouse, I.H.; Lardin, H.A.; Wenthold, P.G., Gas-phase ion chemistry and ion thermochemistry of phenyltrifluorosilane, Int. J. Mass Spectrom., 2003, 227, 3, 303-314, https://doi.org/10.1016/S1387-3806(03)00080-0 . [all data]

DeTuri and Ervin, 1999
DeTuri, V.F.; Ervin, K.M., Competitive threshold collision-induced dissociation: Gas-phase acidities and bond dissociation energies for a series of alcohols, J. Phys. Chem. A, 1999, 103, 35, 6911-6920, https://doi.org/10.1021/jp991459m . [all data]

Notes

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

• Symbols used in this document:
  

  EAneutral	Electron affinity of neutral species
  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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