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A jumping crystal predicted with molecular dynamics and analysed with TLS refinement against powder diffraction data.

ABSTRACT: By running a temperature series of molecular dynamics (MD) simulations starting from the known low-temperature phase, the experimentally observed phase transition in a 'jumping crystal' was captured, thereby providing a prediction of the unknown crystal structure of the high-temperature phase and clarifying the phase-transition mechanism. The phase transition is accompanied by a discontinuity in two of the unit-cell parameters. The structure of the high-temperature phase is very similar to that of the low-temperature phase. The anisotropic displacement parameters calculated from the MD simulations readily identified libration as the driving force behind the phase transition. Both the predicted crystal structure and the phase-transition mechanism were verified experimentally using TLS (translation, libration, screw) refinement against X-ray powder diffraction data.

SUBMITTER: van de Streek J

PROVIDER: S-EPMC6327187 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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A jumping crystal predicted with molecular dynamics and analysed with TLS refinement against powder diffraction data.

van de Streek Jacco J Alig Edith E Parsons Simon S Vella-Zarb Liana L

IUCrJ 20190101 Pt 1

By running a temperature series of molecular dynamics (MD) simulations starting from the known low-temperature phase, the experimentally observed phase transition in a 'jumping crystal' was captured, thereby providing a prediction of the unknown crystal structure of the high-temperature phase and clarifying the phase-transition mechanism. The phase transition is accompanied by a discontinuity in two of the unit-cell parameters. The structure of the high-temperature phase is very similar to that ...[more]

PMID: 30713711

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