Chemical bonds ionization cross section

The authors of Refs. 138 and 139 have shown that the ionization cross section of a complicated molecule can be presented as a sum of ionization cross sections of separate chemical bonds with very good accuracy. Analyzing the experimental data on ionization cross sections of 40 hydrocarbon molecules of different nature, the authors of Ref. 139 have found the effective ionization cross sections of C-H, 7r(C-C), cr(C-C), C-O, and a number of other bonds, which allows one to approximate the ionization cross section of an arbitrary molecule with given chemical bonds with an accuracy of 2%. 

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