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Dynamic tilting in perovskites.

ABSTRACT: A new computational analysis of tilt behaviour in perovskites is presented. This includes the development of a computational program - PALAMEDES - to extract tilt angles and the tilt phase from molecular dynamics simulations. The results are used to generate simulated selected-area electron and neutron diffraction patterns which are compared with experimental patterns for CaTiO₃. The simulations not only reproduced all symmetrically allowed superlattice reflections associated with tilt but also showed local correlations that give rise to symmetrically forbidden reflections and the kinematic origin of diffuse scattering.

SUBMITTER: Handley CM

PROVIDER: S-EPMC9979940 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Dynamic tilting in perovskites.

Handley Christopher M CM Ward Robyn E RE Freeman Colin L CL Reaney Ian M IM Sinclair Derek C DC Harding John H JH

Acta crystallographica. Section A, Foundations and advances 20230123 Pt 2

A new computational analysis of tilt behaviour in perovskites is presented. This includes the development of a computational program - PALAMEDES - to extract tilt angles and the tilt phase from molecular dynamics simulations. The results are used to generate simulated selected-area electron and neutron diffraction patterns which are compared with experimental patterns for CaTiO<sub>3</sub>. The simulations not only reproduced all symmetrically allowed superlattice reflections associated with til ...[more]

PMID: 36862041

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