Molecular dynamics simulations of the O2− ion mobility in dense Ne gas at low temperature: Influence of the repulsive part of the ion-neutral interaction potential

摘要

New Molecular Dynamics simulations have been carried out in order to get aninsight on the physical mechanisms that determine the drift mobility ofnegative Oxygen ions in very dense Neon gas in the supercritical phase close tothe critical point. Two ion-neutral interaction potentials have been used thatdiffer by their repulsive part. We have observed that the potential with aharder repulsive part gives much better agreement with the experimental data.The differences with the softer repulsive potential previously used arediscussed. We propose that the behavior of the ion mobility as a function ofthe gas density is related to the number of neutral atoms loosely bound in thefirst solvation shell around the ion.