Chromium(III) fluoride


Chromium fluoride is an inorganic compound with the chemical formula. It forms several hydrates. The compound is a green crystalline solid that is insoluble in common solvents, but the hydrates and are soluble in water. The anhydrous form sublimes at 1100–1200 °C.

Structures

Like almost all compounds of chromium, these compounds feature octahedral Cr centres. In the anhydrous form, the six coordination sites are occupied by fluoride ligands that bridge to adjacent Cr centres. In the hydrates, some or all of the fluoride ligands are replaced by water.

Production

Chromium fluoride is produced from the reaction of chromium(III) oxide and hydrofluoric acid:
The anhydrous form is produced from hydrogen fluoride and chromic chloride:
Another method of synthesis of involves thermal decomposition of :
A mixed valence compound is also known.

Uses

Chromium fluoride finds some applications as a mordant in textiles and as a corrosion inhibitor. Chromium fluoride catalyzes the fluorination of chlorocarbons by HF.