Interaction of thermally evaporated dipeptides with keV-energy α-particles

Abstract

Abstract Fragmentation of isolated molecular ions of dipeptides produced by alpha-particles was studied by an experimental technique based on time-of-flight analysis of the charge and mass composition of the fragment ions. The study has shown that the N-Glycylglycine sublimation results in the molecule decomposition into cyclo(GlycylGlycyl) and H2O molecule. We have examined a mass-spectrum of the fragments arising in the cyclo(GlycylGlycyl) interaction with α-particles. By analyzing the temperature dependence of the cyclo(GlycylGlycyl) vapor pressure, we have determined sublimation enthalpy ΔHsubl(453K) = (213 ± 9) kJ/mol.