THE OBSERVATION OF UNUSUAL RESONANCE CHANNELS IN THE ELECTRON-ATTACHMENT TO MIXED ARGON OXYGEN CLUSTERS

An additional electron attachment resonance peak, not observable in pure oxygen cluster anions. has been found at an energy of about 11.5 eV for both the stoichiometric Ar(m)(O2)n- and the nonstoichiometric Ar(m)(O2)n-1O cluster anions (produced by electron attachment to mixed argon-oxygen clusters). Two possible competing mechanisms are proposed to explain the appearance of these resonance peaks, i.e. the multiple-collision electron-scavenging mechanism and the core-excited resonance attachment mechanism. From the peak-width analysis it follows that in Ar(m)(O2)n- the first mechanism is dominant, while in Ar(m)(O2)n-1O- the second mechanism seems to be the only one occurring.