Evolutionary exploration of polytypism in lead halide perovskites.

ABSTRACT: The regular ABX₃ cubic perovskite structure is composed of close-packed AX₃ layers stacked along the 〈111〉 axis. An equivalent hexagonal close-packed network can also be formed, in addition to a series of intermediate polytype sequences. Internally, these correspond to combinations of face- and corner-sharing octahedral chains that can dramatically alter the physical properties of the material. Here, we assess the thermodynamics of polytypism in CsPbI₃ and CsPbBr₃. The total energies obtained from density functional theory are used to paramaterize an axial Ising-type model Hamiltonian that includes linear and cubic correlation terms of the pseudo-spin. A genetic algorithm is built to explore the polytype phase space that grows exponentially with

SUBMITTER: Li Z 

PROVIDER: S-EPMC8457387 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature