Platinum tetrafluoride

Platinum tetrafluoride is the inorganic compound with the chemical formula PtF
₄. In the solid state, the compound features platinum(IV) in octahedral coordination geometry.^[2]

Platinum tetrafluoride

Names
IUPAC name Platinum(IV) fluoride
Other names Platinum tetrafluoride Platinous fluoride
Identifiers
CAS Number	13455-15-7
3D model (JSmol)	Interactive image
PubChem CID	139460
CompTox Dashboard (EPA)	DTXSID70158789
InChI InChI=1S/4FH.Pt/h4*1H;/q;;;;+4/p-4 Key: VFKKSKGQZDULMV-UHFFFAOYSA-J
SMILES F[Pt](F)(F)F
Properties
Chemical formula	F4Pt
Molar mass	271.078[1]
Appearance	red-orange solid[1]
Density	7.08 g/cm3 (calc.)[2]
Melting point	600 °C (1,112 °F; 873 K)[1]
Magnetic susceptibility (χ)	+455.0·10−6 cm3/mol
Structure
Crystal structure	Orthorhombic, oF40
Space group	Fdd2, No. 43[2]
Lattice constant	a = 0.9284 nm, b = 0.959 nm, c = 0.5712 nm
Related compounds
Other anions	Platinum(IV) bromide Platinum(IV) chloride
Related compounds	Platinum(V) fluoride Platinum(VI) fluoride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Preparation

The compound was first reported by Henri Moissan by the fluorination of platinum metal in the presence of hydrogen fluoride.^[3] A modern synthesis involves thermal decomposition of platinum hexafluoride.^[4]

Properties

Platinum tetrafluoride vapour at 298.15 K consists of individual molecules. The enthalpy of sublimation is 210 kJmol⁻¹.^[5] Original analysis of powdered PtF₄ suggested a tetrahedral molecular geometry, but later analysis by several methods identified it as octahedral, with four of the six fluorines on each platinum bridging to adjacent platinum centres.^[6]

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.^[7] When heated to a red hot temperature, platinum tetrafluoride decomposes to platinum metal and fluorine gas. When heated in contact with glass, silicon tetrafluoride gas is produced along with the metal.^[7]

Platinum tetrafluoride can form adducts with selenium tetrafluoride and bromine trifluoride.^[7] Volatile crystalline adducts are also formed in combination with BF₃, PF₃, BCl₃, and PCl₃.^[7]

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.^[7] Potassium, rubidium, caesium, and barium salts are insoluble in water.^[7]

References

1. Haynes, William M., ed. (2011). CRC Handbook of Chemistry and Physics (92nd ed.). Boca Raton, FL: CRC Press. p. 4.81. ISBN 1-4398-5511-0.
2. Mueller, B. G.; Serafin, M. (1992). "Single-crystal investigations on PtF₄ and PtF₅". European Journal of Solid State Inorganic Chemistry. 29: 625–633. doi:10.1002/chin.199245006.^{[full citation needed]}
3. Moissan, H. "Platinum tetrafluoride". Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences. 109: 807–9.
4. Slivnik, J. E.; Z̆emva, B.; Druz̆ina, B. (1980). "New syntheses of platinum (IV) and platinum (VI) fluorides". Journal of Fluorine Chemistry. 15 (4): 351. doi:10.1016/S0022-1139(00)81471-2.
5. Bondarenko, A.A; Korobov, M.V; Mitkin, V.N; Sidorov, L.N (March 1988). "Enthalpy of sublimation of platinum tetrafluoride". The Journal of Chemical Thermodynamics. 20 (3): 299–303. doi:10.1016/0021-9614(88)90125-5.
6. "Solid State Structures of the Binary Fluorides of the Transition Metals". Advances in Inorganic Chemistry and Radiochemistry. Vol. 27. Academic Press. 1983. Section V: Tetrafluorides, pages 97–103. ISBN 9780080578767.
7. Derek Harry Lohmann (October 1961). The fluorides of platinum and related compounds (Thesis). University of British Columbia.