Platinum hexafluoride
Platinum hexafluoride is the chemical compound with the formula PtF6, and is one of seventeen known binary hexafluorides. It is a dark-red volatile solid that forms a red gas. The compound is a unique example of platinum in the +6 oxidation state. With only four d-electrons, it is paramagnetic with a triplet ground state. PtF6 is a strong fluorinating agent and one of the strongest oxidants, capable of oxidising xenon and O2. PtF6 is octahedral in both the solid state and in the gaseous state. The Pt-F bond lengths are 185 picometers.[1]
Synthesis
PtF6 was first prepared by reaction of fluorine with platinum metal.[2] This route remains the method of choice.[1]
- Pt + 3 F2 → PtF6
PtF6 can also be prepared by disproportionation of the pentafluoride (PtF5), with the tetrafluoride (PtF4) as a byproduct. The required PtF5 can be obtained by fluorinating PtCl2:
- 2 PtCl2 + 5 F2 → 2 PtF5 + 2 Cl2
- 2 PtF5 → PtF6 + PtF4
Hexafluoroplatinates
Platinum hexafluoride can gain an electron to form the hexafluoroplatinate anion, Template:Chem. It is formed by reacting platinum hexafluoride with relatively uncationisable elements and compounds, for example with xenon to form "Template:Chem" (actually a mixture of Template:Chem, Template:Chem, and Template:Chem), known as xenon hexafluoroplatinate. The discovery of this reaction in 1962 proved that noble gases form chemical compounds. Previous to the experiment with xenon, Template:Chem had been shown to react with oxygen to form [O2]+[PtF6]−, dioxygenyl hexafluoroplatinate.
See also
References
General reading
- Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. Template:ISBN.
Template:Platinum compounds Template:Hexafluorides Template:Fluorine compounds