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MeO anion


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

EAneutral (eV) Method Reference Comment
1.5690 ± 0.0019LPESNee, Osterwalder, et al., 2006 
1.5720 ± 0.0040LPESRamond, Davico, et al., 2000 
1.5680 ± 0.0050LPESOsborn, Leahy, et al., 1998 
1.685 ± 0.094D-EABartmess, Scott, et al., 1979The acidity is 1.2 kcal/mol stronger than that from the D-EA cycle, due to the multi-compound fit for the acidity scale.; value altered from reference due to change in acidity scale
1.570 ± 0.022LPESEngleking, Ellison, et al., 1978Confirmed by high level calculations: Hiraoka, Shimizu, et al., 1995
1.591 ± 0.040PDJanousek, Zimmerman, et al., 1978 
<1.591 ± 0.039PDReed and Brauman, 1975 
2.59998EIAETsuda and Hamill, 1964From MeOMe
0.3816SIPage and Goode, 1969The Magnetron method, lacking mass analysis, is not considered reliable.

Protonation reactions

CH3O- + Hydrogen cation = Methyl Alcohol

By formula: CH3O- + H+ = CH4O

Quantity Value Units Method Reference Comment
Deltar382. ± 2.kcal/molAVGN/AAverage of 6 values; Individual data points
Quantity Value Units Method Reference Comment
Deltar376.02 ± 0.62kcal/molH-TSNee, Osterwalder, et al., 2006gas phase
Deltar376.04 ± 0.55kcal/molH-TSOsborn, Leahy, et al., 1998gas phase
Deltar374.0 ± 2.0kcal/molIMREBartmess, Scott, et al., 1979gas phase; The acidity is 1.2 kcal/mol stronger than that from the D-EA cycle, due to the multi-compound fit for the acidity scale.; value altered from reference due to change in acidity scale
Deltar374.6 ± 2.1kcal/molH-TSHaas and Harrison, 1993gas phase; Both metastable and 50 eV collision energy.
Deltar375.10 ± 0.60kcal/molTDEqMeot-ner and Sieck, 1986gas phase; Experimental entropy: 21.5 eu, 0.6 less than H2O

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.

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]


Notes

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