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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

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

Rahim Warda W Skelton Jonathan M JM Savory Christopher N CN Evans Ivana R IR Evans John S O JSO Walsh Aron A Scanlon David O DO

Chemical science 20200706 30

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 phas ...[more]

PMID: 34909139

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