Atomic-level understanding of a formamidinium hybrid halide perovskite, FAPbBr 3 .

Herein, we show how electron microscopy can provide atomic-level understanding of FAPbBr 3 , where electron diffraction and high-resolution imaging were combined allowing not only the characterization of the pristine material but also the identification of different intermediates upon its structural disintegration. Additionally, a minor tetragonal phase was also identified whose structure was also solved.