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Names | |||
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IUPAC name
Dioxygenyl hexafluoroplatinate
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Other names
Dioxygenyl hexafluoroplatinate(V)
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Identifiers | |||
3D model (
JSmol)
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Properties | |||
F6O2Pt | |||
Molar mass | 341.072 g·mol−1 | ||
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
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Dioxygenyl hexafluoroplatinate is a
compound with formula O2PtF6. It is a
hexafluoroplatinate of the unusual
dioxygenyl cation, O2+, and is the first known compound containing this cation.
[1] It can be produced by the reaction of
dioxygen with
platinum hexafluoride. The fact that PtF
6 is strong enough to oxidise O
2, whose first
ionization potential is 12.2
eV, led
Neil Bartlett to correctly surmise that it might be able to oxidise
xenon (first ionization potential 12.13 eV). This led to the discovery of
xenon hexafluoroplatinate,
[2] which proved that the
noble gases, previously thought to be inert, are able to form chemical compounds.
Dioxygenyl hexafluoroplatinate can be synthesized from the elements by the action of a mixture of
oxygen and
fluorine gas on
platinum sponge at 450 °C.
[1] It can also be prepared by the reaction of
oxygen difluoride (OF
2) with
platinum sponge. At 350 °C,
platinum tetrafluoride is produced; above 400 °C, dioxygenyl hexafluoroplatinate is formed.
[1]
Bartlett demonstrated that it can be synthesized at room temperature by the reaction of oxygen gas with
PtF
6.
[1]
Dioxygenyl hexafluoroplatinate(V) has a
rhombohedral crystal structure at low temperatures, and a cubic structure at high temperatures,
[3] isomorphous to
potassium hexafluoroplatinate(V), KPtF
6. Its ionic lattice is indicated by its insolubility in
carbon tetrafluoride. In its cubic form, the PtF−
6 octahedra are slightly compressed along the three-fold rotational axis, along which the long axis of the [O
2+
cations also lies. Each O+
2 cation is surrounded by 12 fluorine atoms, 6 of which surround it in a puckered six-membered ring, and of the remaining 3 each belong to the two PtF−
6 octahedra lying along the long axis of the cation.
[1]
Dioxygenyl hexafluoroplatinate(V) is a convenient route to prepare other platinum(V) compounds, such as potassium hexafluoroplatinate(V) via reaction with
potassium fluoride in
iodine pentafluoride (IF
5) solution
[3] in which
iodine heptafluoride is produced: