New electron-ion coincidence setup: Fragmentation of acetonitrile following N 1s core excitation

Abstract

A new electron-energy-resolved electron-ion coincidence setup was developed based on the Scienta SES-100 hemispherical electron analyzer and a Wiley–McLaren type ion TOF spectrometer. With this setup, an electron-ion coincidence study of gas-phase acetonitrile ( CH 3 CN ) was performed using synchrotron radiation. The fragmentation patterns in coincidence with resonant Auger electrons were recorded, following N 1s core excitations to the molecular orbital of the π CN ∗ character. Also the dissociation of doubly charged molecular ions produced after normal Auger decay of N 1 s − 1 core-hole states was investigated from PEPICO and PEPIPICO maps. Kinetic energy releases in some reactions were determined with the aid of Monte-Carlo modelling.