Negative-Ion Mass Spectra and Electron Affinities

The mono and dichlorobenzenes do not show parent negative ions at 373 K or 523 K. This does not imply that the electron affinity is negative, but rather that other processes occur. Both dissociative and nondissociative capture are observed for the tri and tetrachlorobenzenes. For the penta and hexachlorobenzenes no dissociative attachment is observed. For the biphenyls with two chlorines ion molecule reactions predominate. With three chlorines, two on one ring and the third on the other ring, molecular ions are observed at 373 K. With four or more chlorines molecular ions are observed at both high and low temperatures, and dissociative electron 

TABLE 11.11 Electron Affinities of Chloronaphthalenes from Reduction Potentials and CURES-EC [22 and this work] 

TABLE 11.12 Electron Affinities (in eV) of Chlorinated Biphenyls from Reduction Potentials and CURES-EC 

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