A mass-spectrometric apparatus for isotope separation purposes

A new experimental apparatus for mass-spectrometric investigation of atomic and molecular ion fragment production in the dissociative ionization of various isotope-differing molecular species is described. Using a quadrupole mass-spectrometer the relative ion yields of a number of dissociative ionization (DI) products for the H2O, D2O, C6H6 and C6HD5 molecules have been measured indicating different behaviours of DI cross sections. The appearance thresholds of a series of ionic fragment groups have been determined. (orig.)