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arXiv · 2311.12966

Polytypism of Incommensurately Modulated Structures of Crystalline Bromine upon Molecular Dissociation under High Pressure

Yuqing Yin·Andrey Aslandukov·Maxim Bykov·Dominique Laniel·Alena Aslandukova·Anna Pakhomova·Timofey Fedotenko·Wenju Zhou·Fariia Iasmin Akbar·Michael Hanfland·Konstantin Glazyrin·Carlotta Giacobbe·Eleanor Lawrence Bright·Gaston Garbarino·Zhitai Jia·Natalia Dubrovinskaia·Leonid Dubrovinsky
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Abstract

Polytypism of incommensurately modulated structures was hitherto unobserved. Here, we found the phenomenon in simple halogen systems of bromine and iodine upon molecular dissociation in the solids under pressure. Single-crystal synchrotron X-ray diffraction in laser heated diamond anvil cells pressurised up to 112 GPa revealed a number of allotropes of bromine and iodine including polytypes of Br-III{\gamma} (Fmmm(00{\gamma})s00) with {\gamma} varying within 0.18 to 0.3.

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Yuqing Yin, Andrey Aslandukov, Maxim Bykov, Dominique Laniel, Alena Aslandukova, Anna Pakhomova, Timofey Fedotenko, Wenju Zhou, Fariia Iasmin Akbar, Michael Hanfland, Konstantin Glazyrin, Carlotta Giacobbe, Eleanor Lawrence Bright, Gaston Garbarino, Zhitai Jia, Natalia Dubrovinskaia, Leonid Dubrovinsky. 2023-11-21. Polytypism of Incommensurately Modulated Structures of Crystalline Bromine upon Molecular Dissociation under High Pressure. https://arxiv.org/abs/2311.12966

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