A huge congratulations to Michael, James, and Laila for publishing their work on halide segregation in perovskite nanocrystals in J. Phys. Chem. Letters! Michael performed some excruciatingly difficult measurements on perovskite nanocrystals after halide segregation, trapping them in a segregated state and using a traditional transient absorption spectrometer to find that their Auger recombination rates increased. Michael modeled the wavefunctions in nanocrystals as a function of their halide distributions to find that in a NC comprised of both iodides and bromides, the iodides must be segregating to the core of the NC, as opposed to segregating to its surface. This means that it’s likely the strain induced by the exciton that is causing halide segregation, not just individual iodides migrating to the surface – a surprise to all of us! Congrats, Michael!