Spontaneous Octahedral Tilting in the Cubic Inorganic Caesium Halide Perovskites CsSnX${}_3$ and CsPbX${}_3$ (X = F, Cl, Br, I)

Ruo Xi Yang, Jonathan M. Skelton, E. Lora da Silva +2

The local crystal structures of many perovskite-structured materials deviate from the average space group symmetry. We demonstrate, from lattice-dynamics calculations based on quan…