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
3D model (JSmol)
Properties
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]
+455.0·10−6 cm3/mol
Structure
Orthorhombic, oF40
Fdd2, No. 43[2]
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]

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 1439855110.
  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.
  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. 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.


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.