ELECTRON-IMPACT IONIZATION OF THE NUCLEIC ACID BASES MOLECULES M.I. Sukhoviya, I.A. Shondoly, M.I. Shafranyosh, L.L. Shimon Department of Physics, Uzhgorod State University, Uzhgorod, Ukraine Electron-impact ionization of the complementare nucleic acid bases were investigated in gas phase. Ionization functions of the thymine and adenine molecules were studied at the energy range from 0 up to 100 eV.