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The polymerization of nitrogen in Li₂N₂ at high pressures.

ABSTRACT: The polymerization of nitrogen can be used as high energy density materials. The crystal structures of Li₂N₂ at high pressures are explored by using the first-principles method combined with evolutionary algorithm. The phase transitions Pmmm → Immm → Pnma → Cmcm-1 → I4₁/acd are predicted in the pressure range of 0-300 GPa. Enthalpy calculations reveal that the tetragonal phase I4₁/acd containing the spiral nitrogen chains is stable above 242 GPa, indicating that the polymerization of nitrogen is realized in Li₂N₂ under pressure.

SUBMITTER: Zhang J

PROVIDER: S-EPMC6120935 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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The polymerization of nitrogen in Li2N2 at high pressures.

Zhang Jie J Wang Xianlong X Yang Kaishuai K Cheng Ya Y Zeng Zhi Z

Scientific reports 20180903 1

The polymerization of nitrogen can be used as high energy density materials. The crystal structures of Li2N2 at high pressures are explored by using the first-principles method combined with evolutionary algorithm. The phase transitions Pmmm → Immm → Pnma → Cmcm-1 → I41/acd are predicted in the pressure range of 0-300 GPa. Enthalpy calculations reveal that the tetragonal phase I41/acd containing the spiral nitrogen chains is stable above 242 GPa, indic ...[more]

PMID: 30177855

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