Xenon Suboxides Stable under Pressure.
We present results from first-principles calculations on solid xenon-oxygen compounds under pressure. We find that the xenon suboxide Xe3O2 is the first compound to become more stable than the elements, at around P = 75 GPa. Other, even more xenon-rich compounds follow at higher pressures, while no region of enthalpic stability is found for the monoxide XeO. We establish the spectroscopic fingerprints of a variety of structural candidates for a recently synthesized xenon-oxygen compound at atmospheric pressure and, on the basis of the proposed stoichiometry XeO2, suggest an orthorhombic structure that comprises extended sheets of square-planar-coordinated xenon atoms connected through bent Xe-O-Xe linkages.
†Centre for Science under Extreme Conditions, School of Physics and Astronomy, The University of Edinburgh, Edinburgh EH9 3FD, United Kingdom.
Andreas
A
Hermann
‡Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study and The Institute for Natural and Mathematical Sciences, Massey University Albany, Private Bag 102904, Auckland 0745, New Zealand.
Peter
P
Schwerdtfeger
crystal structure prediction; density functional theory; noble gas reactivity; oxygen; pressure; xenon