Terbium(III) chloride

Terbium(III) chloride (TbCl3) is a chemical compound. In the solid state TbCl3 has the YCl3 layer structure. Terbium(III) chloride frequently forms a hexahydrate.

Preparation
The hexahydrate of terbium(III) chloride can be obtained by the reaction of terbium(III) oxide and hydrochloric acid:


 * Tb2O3 + 6 HCl → 2 TbCl3 + 3 H2O

It can also be obtained by direct reaction of the elements:


 * 2 Tb + 3 Cl2 → 2 TbCl3

Properties
Terbium(III) chloride is a white, hygroscopic powder. It crystallizes in an orthorhombic plutonium(III) bromide crystal structure with space group Cmcm (No. 63). It can form a complex Tb(gly)3Cl3·3H2O with glycine.

Applications
The hexahydrate plays an important role as an activator of green phosphors in color TV tubes and is also used in specialty lasers and as a dopant in solid-state devices.

Hazards
Terbium(III) chloride causes hyperemia of the iris. Conditions/substances to avoid are: heat, acids and acid fumes.