Multiscale modeling of electrospray ion emission

Abstract

A multi-scale approach to electrospray ion source modeling has been developed. The evolution of a single-emitter electrospray plume in a pure ionic regime is simulated with a combination of electrohydrodynamic fluids and n-body particle modeling. Simulations are performed for the ionic liquid, EMI-BF4, firing in a positive pure-ion mode. The metastable nature of ion clusters is captured using an ion fragmentation model informed by molecular dynamics simulations and experimental data. Results are generated for three operating points (120, 324, and 440 nA) and are used to predict performance relevant properties, such as the divergence angle and the extractor surface impingement rate. Comparisons to experimental data recorded at similar operating points are provided.