High-Pressure Reactivity of Kr and F2—Stabilization of Krypton in the +4 Oxidation State

Crystals

Dominik Kurzydłowski¹  Magdalena Sołtysiak²  Aleksandra Dżoleva²  Patryk Zaleski-Ejgierd³ 

[1] Centre of New Technologies, University of Warsaw, Warsaw 02-097 , Poland;Faculty of Mathematics and Natural Sciences, Cardinal Stefan Wyszyński University, Warsaw 01-038 , Poland;Faculty of Physics, IFT, University of Warsaw, Warsaw 02-093, Poland;

关键词: krypton;    fluorine;    high-pressure;    Density Functional Theory;    phase transitions;    noble gas chemistry;    molecular crystals, fluorides;   

DOI  :  10.3390/cryst7110329

来源: DOAJ

【 摘 要 】

Since the synthesis of the first krypton compound, several other Kr-bearing connections have been obtained. However, in all of them krypton adopts the +2 oxidation state, in contrast to xenon which forms numerous compounds with an oxidation state as high as +8. Motivated by the possibility of thermodynamic stabilization of exotic compounds with the use of high pressure (exceeding 1 GPa = 10 kbar), we present here theoretical investigations into the chemistry of krypton and fluorine at such large compression. In particular we focus on krypton tetrafluoride, KrF4, a molecular crystal in which krypton forms short covalent bonds with neighboring fluorine atoms thus adopting the +4 oxidation state. We find that this hitherto unknown compound can be stabilized at pressures below 50 GPa. Our results indicate also that, at larger compressions, a multitude of other KrmFn fluorides should be stable, among them KrF which exhibits covalent Kr–Kr bonds. Our results set the stage for future high-pressure synthesis of novel krypton compounds.

【 授权许可】

Unknown