Missing phases in CsPbCl3 explored using high-pressure

Lead-halide perovskites are attractive candidates for applications such as solar cells, light-emitting diodes, and photodetectors, due to their excellent photoelectric efficiencies. As is the case with many of this class of material, CsPbCl3 is highly sensitive to external factors, with four known polymorphs at ambient pressure. At elevated pressures, the story is more complicated, with two additional phases identified up to 2 GPa at 300 K, both highly dependent on the route taken to get there, with structures unknown. Understanding this material at elevated pressures is important to aid our understanding of the effects of external strains on this material, which is essential for potential applications in thin-film devices. We aim to revisit this material to extend the known pressure/temperature phase diagram, to better understand the nature of these missing phases at ambient temperature.