title: 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-N2mixtures 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.
authors.affiliation: Center for High Pressure Science &Technology Advanced Research, Shanghai, 201203, P.R. China.
authors.forename: Ross T
authors.initials: RT
authors.lastname: Howie
authors.affiliation: Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
authors.forename: Robin
authors.initials: R
authors.lastname: Turnbull
authors.affiliation: Center for High Pressure Science &Technology Advanced Research, Shanghai, 201203, P.R. China.
authors.forename: Jack
authors.initials: J
authors.lastname: Binns
authors.affiliation: Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
authors.forename: Mungo
authors.initials: M
authors.lastname: Frost
authors.affiliation: Center for High Pressure Science &Technology Advanced Research, Shanghai, 201203, P.R. China.
authors.forename: Philip
authors.initials: P
authors.lastname: Dalladay-Simpson
authors.affiliation: Centre for Science at Extreme Conditions and School of Physics and Astronomy, University of Edinburgh, Edinburgh, UK.
authors.forename: Eugene
authors.initials: E
authors.lastname: Gregoryanz