tin(IV) fluoride
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| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 428754510
| ImageFile = Niobtetrafluorid.png
| ImageSize = 250px
| ImageCaption = Unit cell of tin(IV) fluoride
| ImageAlt = Unit cell of tin(IV) fluoride
| IUPACName = tin(IV) fluoride
| OtherNames = stannic fluoride, tin tetrafluoride
| Section1 = {{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|??}}
| CASNo = 7783-62-2
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = HNZ2XMR1ZF
| PubChem = 134654
| EINECS = 232-016-0
| InChI = 1S/4FH.Sn/h4*1H;/q;;;;+4/p-4
| SMILES = [F-].[F-].[F-].[F-].[Sn+4]
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| Section2 = {{Chembox Properties
| Formula = SnF4
| MolarMass = 194.704 g/mol
| Appearance = white solid
| Density = 4.78 g / cm3
| MeltingPt = above 700 °C (sublimes)
| BoilingPt =
| Solubility =
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| Section3 = {{Chembox Structure
| CrystalStruct = Tetragonal, tI10
| SpaceGroup = I4/mmm, No. 139
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| Section7 = {{Chembox Hazards
| GHSPictograms = {{GHS05}}{{GHS07}}
| GHSSignalWord = Danger
| HPhrases = {{H-phrases|H302|H312|H314|H332}}
| PPhrases = {{P-phrases|P260|P261|P264|P270|P271|P280|P301+P317|P301+P330+P331|P302+P352|P302+P361+P354|P304+P340|P305+P354+P338|P316|P317|P321|P330|P362+P364|P363|P405|P501}}
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| Section9 = {{Chembox Related
| OtherAnions = Tin(IV) chloride
Tin(IV) bromide
Tin(IV) iodide
| OtherCations = Carbon tetrafluoride
Silicon tetrafluoride
Germanium tetrafluoride
Tin tetrafluoride
Lead tetrafluoride
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Tin(IV) fluoride is a chemical compound of tin and fluorine with the chemical formula SnF4. It is a white solid. As reflected by its melting point above 700 °C, the tetrafluoride differs significantly from the other tetrahalides of tin.{{cite book | last=Greenwood |first = N. N. |author2=Earnshaw, A. | title=Chemistry of the Elements | url=https://archive.org/details/chemistryelement00earn_612 | url-access=limited |edition = 2nd |publisher=Oxford:Butterworth-Heinemann | year=1997 | isbn=0-7506-3365-4 |pages=[https://archive.org/details/chemistryelement00earn_612/page/n402 381] }}
Synthesis and reaction
SnF4 can be prepared by the reaction of tin(IV) chloride with anhydrous hydrogen fluoride:
:SnCl4 + 4HF → SnF4 + 4HCl
When treated with alkali metal fluorides (e.g. KF), tin(IV) fluoride forms hexafluorostannates:
:{{chem2|SnF4 + 2 KF -> K2SnF6}}
In K2SnF6, tin adopts an octahedral geometry.
Otherwise, SnF4 behaves as a Lewis acid forming a variety of adducts with the formula L2·SnF4 and L·SnF4.{{cite book | last = Holleman | first = A. F. |author2=Wiberg, E. |author3=Wiberg, N. | title=Inorganic Chemistry, 1st Edition | publisher=Academic Press | year=2001 | isbn=0-12-352651-5|pages=908}}
Structure
Unlike the heavier tin tetrahalides, which contain tetrahedrally coordinated tin, tin(IV) fluoride contains octahedrally coordinated tin. The octahedra share four corners. There are two terminal, unshared, fluorine atoms trans to one another.Inorganic Chemistry [Paperback],2d Edition, Housecroft, Sharpe, 2004, Pearson Education {{ISBN|0130399132}}, {{ISBN|978-0130399137}} The melting point of SnF4 is much higher (700 °C) than the other tin(IV) halides: (SnCl4, −33.3 °C; SnBr4, 31 °C; SnI4, 144 °C). The structure can also be contrasted with the tetrafluorides of the lighter members of group 14, (CF4, SiF4 and GeF4), all of which in the solid state form molecular crystals.
See also
References
{{reflist}}
{{Tin compounds}}
{{fluorides}}