Scaling law investigation on dissociation ratios of N2O, CF4, SF6 under 15–30 keV H−, D−, C−, O− impact

Abstract

The relative dissociation ratios of N2O, CF4, and SF6 are measured under 15–30 keV D− impact. The recoil ions emitted from target molecules are detected and recorded by a time of flight mass spectrometer, in coincidence with the detection of scattered projectiles in two channels, single electron loss and double electron loss, respectively. Together with the data of H−, C−, O− incidence, the ratios of atomic ions produced from target molecules can be scaled by nuclear charges of the incident negative ions (Z) and their impact velocities (v). The ratios divided by Z or Z1/3 or Z2/3 all change linearly with v. Moreover, compared with the center atoms in the target molecule, dissociation of the outer atoms show greater dependence on the nuclear charges of incident negative ions.