Nanowires play a central role in the research on sensing, photovoltaics, nanoelectronics and catalysis. Alloying Au nanowires with other metals is expected to enhance the stability over pristine wires, which currently hampers applications. This research line is dedicated to the mapping of the chemical composition in alloy nanowires, which is essential to understand and taylor their physical properties for electrical and catalytic applications. Momentum-resolved STEM is in principle capable of this in terms of evaluating the distinct angular dependence of scattered intensity, but lacks a quantitative understanding of electron scattering at low angles. Improving theoretical models and simulation approaches in this angle regime is hence a key challenge of this project and a paradigm demonstration how fundamental and applied science can complement each other.