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Discovery of Two Polymorphs of TiP₄ N₈ Synthesized from Binary Nitrides.

ABSTRACT: TiP₄ N₈ was obtained from the binary nitrides TiN and P₃ N₅ upon addition of NH₄ F as a mineralizer at 8 GPa and 1400 °C. An intricate interplay of disorder and polymorphism was elucidated by in situ temperature-dependent single-crystal X-ray diffraction, STEM-HAADF, and the investigation of annealed samples. This revealed two polymorphs, which consist of dense networks of PN₄ tetrahedra (degree of condensation κ=0.5) and either augmented triangular TiN₇ prisms or triangular TiN₆ prisms for α- and β-TiP₄ N₈ , respectively. The structures of TiP₄ N₈ exhibit body-centered tetragonal (bct) framework topology. DFT calculations confirm the measured band gaps of α- and β-TiP₄ N₈ (1.6-1.8 eV) and predict the thermochemistry of the polymorphs in agreement with the experiments.

SUBMITTER: Eisenburger L

PROVIDER: S-EPMC9310718 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Discovery of Two Polymorphs of TiP4 N8 Synthesized from Binary Nitrides.

Eisenburger Lucien L Weippert Valentin V Paulmann Carsten C Johrendt Dirk D Oeckler Oliver O Schnick Wolfgang W

Angewandte Chemie (International ed. in English) 20220228 19

TiP4 N8 was obtained from the binary nitrides TiN and P3 N5 upon addition of NH4 F as a mineralizer at 8 GPa and 1400 °C. An intricate interplay of disorder and polymorphism was elucidated by in situ temperature-dependent single-crystal X-ray diffraction, STEM-HAADF, and the investigation of annealed samples. This revealed two polymorphs, which consist of dense networks of PN4 tetrahedra (degree of condensation κ=0.5) and either a ...[more]

PMID: 35179291

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