Polymorph exploration of bismuth stannate using first-principles phonon mode mapping.

ABSTRACT: Accurately modelling polymorphism in crystalline solids remains a key challenge in computational chemistry. In this work, we apply a theoretically-rigorous phonon mode-mapping approach to understand the polymorphism in the ternary metal oxide Bi2Sn2O7. Starting from the high-temperature cubic pyrochlore aristotype, we systematically explore the structural potential-energy surface and recover the two known low-temperature phases alongside three new metastable phases, together with the transition pathways connecting them. This first-principles lattice-dynamics method is completely general and provides a practical means to identify and characterise the stable polymorphs and phase transitions in materials with complex crystal structures.

SUBMITTER: Rahim W 

PROVIDER: S-EPMC8617592 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature