Three-dimensional kinetic energy distributions of ions using a retarding potential analyser. Analysis of discrimination effects by ion trajectory simulations

This paper presents a method of extracting three-dimensional kinetic energy distributions from retarding potential curves, suitable for analysing low kinetic energy releases. Trajectory calculations were performed which led t o an analytical function correcting for the influence of discrimination aga inst ions with velocity components perpendicular to the retarding field dir ection. The analysis of the thermal kinetic energy distribution of molecula r vinyl bromide ions confirms the computed correcting factor. Copyright (C) 1999 John Wiley & Sons, Ltd.