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Pressure-induced planar N6 rings in potassium azide.

ABSTRACT: The first-principles method and the evolutionary algorithm are used to identify stable high pressure phases of potassium azide (KN3). It has been verified that the stable phase with space group I4/mcm below 22 GPa, which is consistent with the experimental result, will transform into the C2/m phase with pressure increasing. These two phases are insulator with N(-)(3) anions. A metallic phase with P6/mmm symmetry is preferred above 40 GPa, and the N atoms in this structure form six-membered rings which are important for understanding the pressure effect on N(-)(3) anions and phase transitions of KN3. Above the studied pressure (100 GPa), a polymerization of N6 rings may be obtained as the result of the increasing compactness.

SUBMITTER: Zhang J

PROVIDER: S-EPMC3950634 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Pressure-induced planar N6 rings in potassium azide.

Zhang Jie J Zeng Zhi Z Lin Hai-Qing HQ Li Yan-Ling YL

Scientific reports 20140312

The first-principles method and the evolutionary algorithm are used to identify stable high pressure phases of potassium azide (KN3). It has been verified that the stable phase with space group I4/mcm below 22 GPa, which is consistent with the experimental result, will transform into the C2/m phase with pressure increasing. These two phases are insulator with N(-)(3) anions. A metallic phase with P6/mmm symmetry is preferred above 40 GPa, and the N atoms in this structure form six-membered rings ...[more]

PMID: 24619232

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