Electron-impact Mass-spectrometry of Ethyl-esters of Halogenated Acetic-acids

The behaviour of a series of differently halogenated acetic acid ethyl esters was studied using electron impact and metastable ion techniques. The presence of different halogens strongly influences the fragmentation pathways and also the kinetic energy release values associated with some decomposition routes. By mass-analysed ion kinetic energy spectrometry, a composite metastable peak was detected for the transition CF2BrCO+ --> CF2Br+, and rationalized on the basis of two different structures for the precursor ion.