Formation of SO−2, SO2·O− and SO2·SO− by electron attachment to van der waals SO2 clusters

SO − 2 , SO 2 ·O − and SO 2 ·SO − are produced by electron attachment to SO 2 clusters under single collision conditions. SO − 2 , which is not produced at all in low-pressure ion sources, is more abundant than SO 2 ·O − and SO 2 ·SO − . Measured relative attachment cross sections for these ions show significant differences when compared to O − and SO − produced by attachment to SO 2 , i.e. the first resonance is very efficiently quenched in favor of SO − 2 production. This is in contrast to previous findings in O 2 , CO 2 and N 2 O.