Platinum tetrafluoride is the
inorganic compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''.
Inorgan ...
with the chemical formula . In the solid state, the compound features platinum(IV) in
octahedral coordination geometry.
Preparation
The compound was first reported by
Henri Moissan by the
fluorination
In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. ...
of platinum metal in the presence of
hydrogen fluoride
Hydrogen fluoride (fluorane) is an Inorganic chemistry, inorganic compound with chemical formula . It is a very poisonous, colorless gas or liquid that dissolves in water to yield hydrofluoric acid. It is the principal industrial source of fluori ...
. A modern synthesis involves thermal decomposition of
platinum hexafluoride.
Properties
Platinum tetrafluoride vapour at 298.15 K consists of individual molecules. The enthalpy of sublimation is 210 kJmol
−1.
Original analysis of powdered PtF
4 suggested a
tetrahedral molecular geometry
In a tetrahedral molecular geometry, a central atom is located at the center with four substituents that are located at the corners of a tetrahedron. The bond angles are arccos(−) = 109.4712206...° ≈ 109.5° when all four substituents are ...
, but later analysis by several methods identified it as octahedral, with four of the six fluorines on each platinum bridging to adjacent platinum centres.
Reactions
A solution of platinum tetrafluoride in water is coloured reddish brown, but it rapidly decomposes, releasing heat and forming an orange coloured
platinum dioxide hydrate precipitate and fluoroplatinic acid.
[
When heated to a red hot temperature, platinum tetrafluoride decomposes to platinum metal and fluorine gas. When heated in contact with glass, ]silicon tetrafluoride
Silicon tetrafluoride or tetrafluorosilane is a chemical compound with the formula Si F4. This colorless gas is notable for having a narrow liquid range: its boiling point is only 4 °C above its melting point. It was first prepared in 1771 ...
gas is produced along with the metal.[
Platinum tetrafluoride can form adducts with ]selenium tetrafluoride
Selenium tetrafluoride ( Se F4) is an inorganic compound. It is a colourless liquid that reacts readily with water. It can be used as a fluorinating reagent in organic syntheses (fluorination of alcohols, carboxylic acids or carbonyl compounds) an ...
and bromine trifluoride.[
]
Related compounds
The fluoroplatinates are salts containing the PtF62− ion. Fluoroplatinic acid H2PtF6 forms yellow crystals that absorb water from the air. Ammonium, sodium, magnesium, calcium, strontium, and rare earth including lanthanum fluoropalatinate salts are soluble in water.[ Potassium, rubidium, caesium, and barium salts are insoluble in water.][
]
References
{{Fluorides
Fluorides,4
Fluorides
Platinum group halides