J. Vacher, F. Jorand, N. Blin-Simiand
Jul 15, 2010
Citations
1
Influential Citations
10
Citations
Journal
International Journal of Mass Spectrometry
Abstract
Abstract Electron impact ionization of n -heptane was studied using mass spectrometry. Cross-sections for the formation of molecular ion and ionic fragments are measured between 10 eV and 86 eV with a total cross-section of 1.5 × 10 −16 cm 2 towards 50 eV. The molecular ion is the most abundant below 16 eV. The present results display good agreement between the measured total ionization cross-sections and the calculated one with the BEB model. Five ions C n H 2 n +1 + (2 ≤ n ≤ 6) result from a simple C–C bond split in the molecular ion. C 3 H 7 + , identified as isopropyl cation, is the most abundant of the ionic species above 16 eV. Four ions C n H 2 n + (2 ≤ n ≤ 5) result from a C–C bond split with H-atom rearrangement. C 3 H 6 + , identified as propene cation, is the most abundant of these four cations above 35 eV. Five other ions, C n H 2 n −1 + (2 ≤ n ≤ 4), cyclopropenyl and methyl cations may result from the ionization of C 4 H 9 , the major alkyl issued from the fragmentation of the molecular ion.