Tin(IV) fluoride

Tin(IV) fluoride
Names
Unit cell of tin(IV) fluoride
IUPAC name tin(IV) fluoride
Other names stannic fluoride, tin tetrafluoride
Identifiers
CAS Number	7783-62-2^Y
3D model (JSmol)	Interactive image
ECHA InfoCard	100.029.105
EC Number	232-016-0
PubChem CID	134654
UNII	HNZ2XMR1ZF^Y
InChI InChI=1S/4FH.Sn/h4*1H;/q;;;;+4/p-4
SMILES [F-].[F-].[F-].[F-].[Sn+4]
Properties
Chemical formula	SnF₄
Molar mass	194.704 g/mol
Appearance	white solid
Melting point	above 700 °C (sublimes)
Structure
Crystal structure	Tetragonal, tI10
Space group	I4/mmm, No. 139
Related compounds
Other anions	Tin(IV) chloride Tin(IV) bromide Tin(IV) iodide
Other cations	Carbon tetrafluoride Silicon tetrafluoride Germanium tetrafluoride Tin tetrafluoride Lead tetrafluoride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is ^YN ?) Infobox references

Chemical compound

Tin(IV) fluoride is a chemical compound of tin and fluorine with the chemical formula SnF₄ and is a white solid with a melting point above 700 °C.^[1]

SnF₄ can be prepared by the reaction of tin metal with fluorine gas:^[2]

Sn + 2F₂ → SnF₄

However, a passivating metal fluoride layer will be created and the surface will eventually become unreactive. An alternative synthesis is the reaction of SnCl₄ with anhydrous hydrogen fluoride:^[1]

SnCl₄ + 4HF → SnF₄ + 4HCl

With alkali metal fluorides (e.g. KF) hexafluorostannates are produced (e.g.K₂SnF₆), which contain the octahedral SnF₆²⁻ anion. SnF₄ behaves as a Lewis acid and adducts L₂·SnF₄ and L·SnF₄ have been produced.^[2]

Structure

Unlike the other tin tetrahalides, tin(IV) chloride, tin(IV) bromide, and tin(IV) iodide, which contain tetrahedrally coordinated tin, tin(IV) fluoride contains planar layers of octahedrally coordinated tin, where the octahedra share four corners and there are two terminal, unshared, fluorine atoms trans to one another.^[3] The melting point of SnF₄ is much higher (700 °C) than the other tin(IV) halides which are relatively low melting, (SnCl₄, −33.3 °C; SnBr₄, 31 °C; SnI₄, 144 °C).^[1] The structure can also be contrasted with the tetrafluorides of the lighter members of group 14, (CF₄, SiF₄ and GeF₄) which in the solid state form molecular crystals.^[2]

References

^ ^a ^b ^c Greenwood, N. N.; Earnshaw, A. (1997). Chemistry of the Elements (2nd ed.). Oxford:Butterworth-Heinemann. pp. 381. ISBN 0-7506-3365-4.
^ ^a ^b ^c Holleman, A. F.; Wiberg, E.; Wiberg, N. (2001). Inorganic Chemistry, 1st Edition. Academic Press. p. 908. ISBN 0-12-352651-5.
^ Inorganic Chemistry [Paperback],2d Edition, Housecroft, Sharpe,2004, Pearson Education ISBN 0130399132, ISBN 978-0130399137