Фторид цезия: свойства, структура и применение

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| Name = Caesium fluoride
| ImageFile = Caesium fluoride. jpg
| ImageName = Caesium fluoride
| ImageFile1 = Caesium fluoride 3D ionic. png
| ImageName1 = Caesium fluoride
| IUPACName = Caesium fluoride
| OtherNames = Cesium fluoride
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| Section3 = Chembox Structure
| Coordination = Octahedral
| CrystalStruct = cubic, cF8
| SpaceGroup = Fmm, No. 225
| LattConst a = 0.6008 nm
| Entropy = 92.8 J/mol·K The compound is noteworthy from the pedagogical perspective as caesium also has the highest electropositivity of all commonly available elements and fluorine has the highest electronegativity.

Caesium fluoride has the halite structure, which means that the Cs+ and F− pack in a cubic closest packed array as do Na+ and Cl− in sodium chloride. CsF gives higher yields in Knoevenagel condensation reactions than KF or NaF.

Caesium fluoride serves as a source of fluoride in organofluorine chemistry. Similarly to potassium fluoride, CsF reacts with hexafluoroacetone to form a stable perfluoroalkoxide salt. It will convert electron deficient aryl chlorides to aryl fluorides (Halex process), although potassium fluoride is more commonly used.

Due to the strength of the Si–F bond, fluoride is useful for desilylation reactions, i. e., cleavage of Si O bonds in organic synthesis. CsF is commonly used for such reactions. Solutions of caesium fluoride in THF or DMF attack a wide variety of organosilicon compounds to produce an organosilicon fluoride and a carbanion, which can then react with electrophiles, for example: Contact with acid should be avoided, as this forms highly toxic/corrosive hydrofluoric acid. The caesium ion (Cs+) and caesium chloride are generally not considered toxic.