Mass spectrometry: the mass spectrum of methanol. Part I. Thermochemical information
1968; Elsevier BV; Volume: 1; Issue: 1 Linguagem: Inglês
10.1016/0020-7381(68)80001-4
ISSN1873-3034
AutoresJ. H. Beynon, Alain Fontaine, Gabriel Lester,
Tópico(s)Spectroscopy and Quantum Chemical Studies
ResumoThe Stages in the electron-impact induced fragmentation of the methanol molecule-ion have been elucidated by the study, using a double-focussing mass spectrometer, of methanol and the three deuterated analogues CH3OD, CD3OH and CD3OD. The exothermic metal-stable ion decompositions (CH3O)+ → (CHO)+ and (CH2O)⨥ → (CHO)− are of special interest since a calculation of relative bond strengths in the ion from the widths of the "metal-stable peaks" accompanying the decompositions gives the apparent result that the bond strength of (O+H) is greater than (O+) as well as the result that (CD) is stronger than (CH). This effect is discussed in detail. An explanation of it in terms of an isotopically-dependent tunnelling process which has the same effect observationally as different degrees of excitation of the decomposing species, is given.
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