Xenon hexafluoroplatinate is the product of the reaction of platinum hexafluoride with

xenon Xenon is a chemical element; it has 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 ...

, in an experiment that proved the chemical reactivity of the

noble gas The noble gases (historically the inert gases, sometimes referred to as aerogens) are the members of Group (periodic table), group 18 of the periodic table: helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn) and, in some ...

es. This experiment was performed by Neil Bartlett at the

University of British Columbia The University of British Columbia (UBC) is a Public university, public research university with campuses near University of British Columbia Vancouver, Vancouver and University of British Columbia Okanagan, Kelowna, in British Columbia, Canada ...

, who formulated the product as "Xe⁺ tF₆sup>−", although subsequent work suggests that Bartlett's product was probably a salt mixture and did not in fact contain this specific salt.

Preparation

"Xenon hexafluoroplatinate" is prepared from xenon and platinum hexafluoride (PtF₆) as gaseous solutions in SF₆. The reactants are combined at 77 K and slowly warmed to allow for a controlled reaction.

Structure

The material described originally as "xenon hexafluoroplatinate" is probably not Xe⁺ tF₆sup>−. The main problem with this formulation is "Xe⁺", which would be a radical and would

dimerize In chemistry, dimerization is the process of joining two identical or similar Molecular entity, molecular entities by Chemical bond, bonds. The resulting bonds can be either strong or weak. Many symmetrical chemical species are described as dim ...

or abstract a

fluorine Fluorine is a chemical element; it has Chemical symbol, symbol F and atomic number 9. It is the lightest halogen and exists at Standard temperature and pressure, standard conditions as pale yellow Diatomic molecule, diatomic gas. Fluorine is extre ...

atom to give XeF⁺. Thus, Bartlett discovered that Xe undergoes chemical reactions, but the nature and purity of his initial mustard yellow product remains uncertain. Further work indicates that Bartlett's product probably also contained products of further oxidation by PtF₆, platinum(V) derivatives PtF₅, eFsup>+ tF₅sup>−, and eFsup>+ t₂F₁₁sup>−. The title "compound" is a salt, consisting of an

octahedral In geometry, an octahedron (: octahedra or octahedrons) is any polyhedron with eight faces. One special case is the regular octahedron, a Platonic solid composed of eight equilateral triangles, four of which meet at each vertex. Many types of i ...

anionic An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...

fluoride Fluoride (). According to this source, is a possible pronunciation in British English. is an Inorganic chemistry, inorganic, Monatomic ion, monatomic Ion#Anions and cations, anion of fluorine, with the chemical formula (also written ), whose ...

complex of

platinum Platinum is a chemical element; it has Symbol (chemistry), symbol Pt and atomic number 78. It is a density, dense, malleable, ductility, ductile, highly unreactive, precious metal, precious, silverish-white transition metal. Its name origina ...

and various xenon cations. It has been proposed that the platinum fluoride forms a negatively charged

polymer A polymer () is a chemical substance, substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeat unit, repeating subunits derived from one or more species of monomers. Due to their br ...

ic anion with xenon fluoride

cation An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...

s. A preparation of "XePtF₆" by reaction of XeF₂ and PtF₄ in anhydrous HF solution results in a solid which has been characterized as a polymeric or

oligomeric In chemistry and biochemistry, an oligomer () is a molecule that consists of a few repeating units which could be derived, actually or conceptually, from smaller molecules, monomer, monomers.Quote: ''Oligomer molecule: A molecule of intermediate ...

anion associated with XeF⁺. Such F-bridged polymeric chains and tetrameric ring with pendant XeF⁺ units have been observed in the crystal structures of the analogous compounds XeCrF₆ (XeF₂∙CrF₄) and XeMnF₆ (XeF₂∙MnF₄), respectively. These structures could serve as structural models for XePtF₆.

History

In 1962, Neil Bartlett discovered that a mixture of platinum hexafluoride gas and oxygen formed a red solid. The red solid turned out to be dioxygenyl hexafluoroplatinate, Bartlett noticed that the ionization energy for O₂ (1175 kJ mol⁻¹) was very close to the ionization energy for Xe (1170 kJ mol⁻¹). He then asked his colleagues to give him some xenon "so that he could try out some reactions", whereupon he established that xenon indeed reacts with PtF₆. Although, as discussed above, the product was probably a mixture of several compounds, Bartlett's work was the first proof that compounds could be prepared from a

. Since Bartlett's observation, many well-defined compounds of xenon have been reported including XeF₂, XeF₄, and XeF₆.

References

{{Platinum compounds Xenon compounds Fluorides Nonmetal halides Coordination complexes Platinum compounds Fluorometallates

Preparation

Structure

History

See also

References