Dynamic mass spectrometer for studies of organic and inorganic molecules.

Experimental technique is described and relative cross-sections of direct and dissociative ionization of CO2, C4H9OH, C2H5OH, CH3OH, C6H12O6 and C7H8 molecules by electron impact in the near-threshold energy range are obtained. The experiment is performed on a setup with ion mass separation based on a monopole mass spectrometer which is proved to be successful for such a sort of experiments. For the incident electron energy range from 7 to 35 eV the energy dependences of cross-section of appearance of the main molecule ions and the fragment ions formed due to its dissociation are given.