Interaction of keV-energy $\alpha$-particles with glycyl–leucine molecules

Radiation-induced damage of isolated glycyl–leucine (C$_{8}$H$_{16}$N$_{2}$O$_{3}$) molecules by the impact of He$^{2+}$ ions has been studied. Relative cross sections of the main processes of charged state variation in collision parties and relative cross sections of fragmentation for singly and doubly charged molecular ions formed due to single collisions between glycyl–leucine molecules and He$^{2+}$ ions have been determined for the first time. Optimized geometry of the molecule and singly charged molecular ion of glycyl–leucine has been calculated by method of density functional theory.