Lanthanum chloride, LaCl₃

Lanthanum chloride, LaCl₃, is a white, crystalline, hygroscopic solid, readily soluble in water.

From an aqueous solution of the chloride, large triclinic crystals (a:b:c = 1.1593:1:0.8659; α = 91°3', β = 114°28', γ = 88°12') of the heptahydrate, LaCl₃.7H₂O, may be obtained. The double salts listed below have been prepared, in addition to those containing metals of Groups IV. and V.: -

LaCl₈.3CsCl.4H₂O(? 5H₂O); LaCl₃.AuCl₃.10H₂O; 2LaCl₃.9HgCl₂.24H₂O; 2LaCl₃.3AuCl₃.21H₂O(?); LaCl₃.3H₂(CN)₂.8H₂O; 2LaCl₃.3PtCl₂.18H₂O; LaCl₃.PtCl₄.13H₂O; 2LaCl₃.3PtCl₄.24H₂O