Mass spectra of a group of normal alkanes, C4 through C8, have been studied as a function of ionizing voltage. Appearance potentials have also been measured for most of the ions. At all voltages the yields of the ion fragments produced by loss of hydrogen atoms and by loss of methyl radicals are surprisingly low relative to their appearance potentials. Since for the lower ionizing voltages it can safely be assumed that there are no significant contributions to the patterns from secondary decompositions, these low yields must indicate a low intrinsic probability for the primary processes by which these ions are formed. For the typical case of n‐pentane, the experimental data have been analyzed from the standpoint of the statistical theory of mass spectra and it is found that frequency factors in the ratio of 1:104:108 must be proposed to account for the yields from the hydrogen atom:methyl radical:ethyl radical extraction processes at low ionizing voltages. The implications of this wide range of frequency ...
[1]
A. L. Wahrhaftig,et al.
THE MASS SPECTRA OF THREE DEUTERATED BUTANOLS
,
1958
.
[2]
Leonard Muldawer,et al.
Electron impact phenomena: by F. H. Field and J. L. Franklin. 349 pages, diagrams, 6 × 9 in.New York, Academic Press, Inc., 1957. Price, $8.50
,
1958
.
[3]
M. Wolfsberg,et al.
Study of the Mass Spectra of the Lower Aliphatic Alcohols
,
1957
.
[4]
H. Eyring,et al.
Absolute Rate Theory for Isolated Systems and the Mass Spectra of Polyatomic Molecules.
,
1952,
Proceedings of the National Academy of Sciences of the United States of America.
[5]
D. Stevenson,et al.
Ionization and dissociation by electronic impact. The ionization potentials and energies of formation of sec.-propyl and tert.-butyl radicals. Some limitations on the method
,
1951
.