“…In work [5], single-ionization cross-sections were calculated for the uracil, thymine, cytosine, adenine, and guanine biomolecules, which are components of nucleic acids. In a series of experimental works (see, for example, works [6][7][8]), the mass spectra obtained at the fragmentation of such amino acids as glycine, methionine, asparagine, tryptophan, proline, alanine, valine, and glutamine were systematically analyzed. In recent works [9,10], the fragmentation dynamics in the process of dissociative ionization of the threonine and tyrosine amino acid molecules by the electron impact was studied experimentally and theoretically, and the appearance energies for some fragment ions were determined.…”