Computational insights into ion mobility spectrometry and electrospray ionization

eng: The topic of the work is the description of the ion dynamics within ion mobility devices as well as electrospray ion sources under different conditions. Depending on the question, various properties of the ions are determined as precisely as possible, e.g. their kinetic energy or reduced ion mobility. For this purpose, the pressure and flow profiles of the background gas are first determined and then used as input parameters for subsequent ion dynamics simulations. To model the neutral gas flow properties, either the continuum model or the Direct Simulation Monte Carlo (DSMC) approach are used. This is represented by the two programs OpenFOAM and SPARTA. For the ion trajectory calculations, SIMION is mostly used, in addition to a customized SPARTA version of the SPARTA framework. Overall, this work consists of three parts:In the first part, a new method for the calculation of reduced ion mobilities and therefore drift velocities in a high-kinetic energy ion mobility spectrometer (HiKE-IMS) is presented. The main feature of this method is that within one simulation run, not only the ions and background gas particles and their interactions are calculated simultaneously, but also simulation parameters as the electric field can be adjusted during runtime.The next part describes a method for determining the effect of a specific ion transfer system on the transferred ions. In this context, a two- and three-dimensional models are compared with each other with regard to the neutral gas flow properties.The third part presents an approach for determining the size distribution of droplets, which are formed within the electrospray ionization (ESI) process, in dependence of the induced ESI current. The simulations presented suggest that it is possible to detect droplets with approximately 10000 charges. In addition, an evaporation model is successfully integrated into an existi++

eng: ng collision model, to obtain more comprehensive results.