Shining light on chemical dynamics from the bulk to single particle, from fs to μs

All of chemical reactivity can, arguably, be encapsulated in two questions: how are molecules oriented and moving, and how are electrons moving? If we answer these questions with high spatiotemporal resolution, then we can understand any chemical reaction occurring in an observed volume. Such a technique that answers this question at single molecule and single particle sensitivity remains out of reach, but I will present two investigations aimed at answering these questions. First, an investigation into how solvent can affect charge transfer, which we studied using bulk solution-phase transient electronic spectroscopy. Second, an investigation in which we show an experiment that measures a single particle's 3D translation with a time resolution of 10 μs and a spatial resolution of ~10 nm in all 3 directions, and measures 3D orientation with 250 μs time resolution. We will close with a vision of future work to enable the spectroscopic interrogation of any non-fluorescent single molecule or nanoparticle as it freely moves in solution.