A significant refinement of the concepts of stopping and scattering of atomic particles with energies less than 100 keV in matter is discussed, which arose when comparing currently available experimental data with the results of computer modeling: the problem of choosing a potential to describe the scattering of particles, clarifying the concepts of nuclear and electronic stopping. The dominant role in the formation of electronic losses of the mechanism associated with the excitation of autoionization states during the rearrangement of molecular shells during collisions is considered. A significant contribution of fast electron emission to the electron loss cross section has been established. The influence of collision parameters on the processes of scattering, sputtering and channeling is analyzed.