Xenon dioxide, or xenon(IV) oxide, is a compound of

xenon Xenon is a chemical element with the symbol Xe and atomic number 54. It is a dense, colorless, odorless noble gas found in Earth's atmosphere in trace amounts. Although generally unreactive, it can undergo a few chemical reactions such as the ...

and

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as ...

with formula XeO₂ which was synthesized in 2011. It is synthesized at 0 °C by hydrolysis of

xenon tetrafluoride Xenon tetrafluoride is a chemical compound with chemical formula . It was the first discovered binary compound of a noble gas. It is produced by the chemical reaction of xenon with fluorine: : Xe + 2 → This reaction is exothermic, rele ...

in aqueous sulfuric acid: XeF4 + 2H2O -> XeO2 + 4HF

Structure

has an extended (chain or network) structure in which xenon and oxygen have

coordination number In chemistry, crystallography, and materials science, the coordination number, also called ligancy, of a central atom in a molecule or crystal is the number of atoms, molecules or ions bonded to it. The ion/molecule/atom surrounding the central io ...

s of four and two respectively. The geometry at xenon is

square planar The square planar molecular geometry in chemistry describes the stereochemistry (spatial arrangement of atoms) that is adopted by certain chemical compounds. As the name suggests, molecules of this geometry have their atoms positioned at the corne ...

, consistent with

VSEPR theory Valence shell electron pair repulsion (VSEPR) theory ( , ), is a model used in chemistry to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms. It is also named the Gillespie-Nyholm the ...

for four ligands and two lone pairs (or AX₄E₂ in the notation of VSEPR theory). In addition, the existence of an XeO₂ molecule was predicted by an ab initio quantum chemistry method several years earlier by Pyykkö and Tamm, but these authors did not consider an extended structure.

Properties

is a yellow-orange solid. It is an unstable compound, with a

half-life Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable at ...

of about two minutes, disproportionating into and xenon gas. Its structure and identity was confirmed by cooling it to −78

°C The degree Celsius is the unit of temperature on the Celsius scale (originally known as the centigrade scale outside Sweden), one of two temperature scales used in the International System of Units (SI), the other being the Kelvin scale. The ...

so that Raman spectroscopy could be performed before it decomposed. :3 XeO₂ → Xe + 2 XeO₃

References

{{Noble gas compounds Oxides Xenon(IV) compounds Inorganic compounds Substances discovered in the 2010s