STOICHIOMETRY OF THE REACTION OF ELECTRONS WITH BROMOTRICHLOROMETHANE IN AN ELECTRON-CAPTURE DETECTOR

A detailed study of the reactions of CCI3Br with electrons and positive ions under conditions existing in an electron capture detector (ECD) is reported. Measurements of ions by atmospheric pressure ionization mass spectrometry (APIMS) indicate that each CCI3Br molecule which undergoes electron capture removes only one electron and the resulting neutral products do not undergo further electron attachment to a significant extent. Also, under the condition where electrons are in abundance in the ECD, it is shown that no significant loss of CCI3Br due to reaction with positive ions occurs. These results lend fundamental support to assumptions of chemical reactivity inherent in the use of the ECD as a gas-phase coulometer. © 1979, American Chemical Society. All rights reserved.