Yttrium(III) fluoride

Yttrium(III) fluoride is an inorganic chemical compound with the chemical formula Y F3. It is not known naturally in 'pure' form. The fluoride minerals containing essential yttrium include tveitite-(Y) (Y,Na)6Ca6Ca6F42 and gagarinite-(Y) NaCaY(F,Cl)6. Sometimes mineral fluorite contains admixtures of yttrium.

Synthesis
YF3 can be produced by reacting fluorine with yttria or yttrium hydroxide with hydrofluoric acid.


 * Y(OH)3 + 3HF → YF3 + 3H2O

Properties
Yttrium(III) fluoride has a refractive index of 1.51 at 500 nm and is transparent in the range from 193 nm to 14,000 nm (i.e. from the UV to IR range).

Pure yttrium can be obtained from yttrium(III) fluoride by reduction with calcium.

Yttrium(III) fluoride crystallizes in the orthorhombic crystal system, with space group Pnma (space group no. 62), with the lattice parameters a = 6.3537 Å, b = 6.8545 Å, c = 4.3953 Å. Yttrium is nine times coordinated by fluorine atoms.

Occurrence and uses
It occurs as the mineral waimirite-(Y).

Yttrium(III) fluoride can be used for the production of metallic yttrium, thin films, glasses and ceramics.

Hazards
Conditions/substances to avoid are: acids, active metals and moisture.