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Formation of xenon-nitrogen compounds at high pressure.

ABSTRACT: Molecular nitrogen exhibits one of the strongest known interatomic bonds, while xenon possesses a closed-shell electronic structure: a direct consequence of which renders both chemically unreactive. Through a series of optical spectroscopy and x-ray diffraction experiments, we demonstrate the formation of a novel van der Waals compound formed from binary Xe-N₂ mixtures at pressures as low as 5?GPa. At 300?K and 5?GPa Xe(N₂)₂-I is synthesised, and if further compressed, undergoes a transition to a tetragonal Xe(N₂)₂-II phase at 14?GPa; this phase appears to be unexpectedly stable at least up to 180?GPa even after heating to above 2000?K. Raman spectroscopy measurements indicate a distinct weakening of the intramolecular bond of the nitrogen molecule above 60?GPa, while transmission measurements in the visible and mid-infrared regime suggest the metallisation of the compound at ~100?GPa.

SUBMITTER: Howie RT

PROVIDER: S-EPMC5066244 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Formation of xenon-nitrogen compounds at high pressure.

Howie Ross T RT Turnbull Robin R Binns Jack J Frost Mungo M Dalladay-Simpson Philip P Gregoryanz Eugene E

Scientific reports 20161017

Molecular nitrogen exhibits one of the strongest known interatomic bonds, while xenon possesses a closed-shell electronic structure: a direct consequence of which renders both chemically unreactive. Through a series of optical spectroscopy and x-ray diffraction experiments, we demonstrate the formation of a novel van der Waals compound formed from binary Xe-N2 mixtures at pressures as low as 5 GPa. At 300 K and 5 GPa Xe(N2)2-I is synthesised, and if further compr ...[more]

PMID: 27748357

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