Erbium(III) sulfate


Erbium sulfate is an erbium compound with the chemical formula. It is a pink crystalline salt, readily absorbing water to form an octahydrate. It is used as a colorant in glass manufacturing and porcelain enamel glazes, as well as a dopant in the production of optical fiber.

Structure

The anhydrous compound forms orthorhombic crystals.
A dimorphic hydrogensulfate exists:
A mixed sulfate-hydrogensulfate ) forms monoclinic crystals.

Synthesis

Erbium sulfate can be prepared by dissolving erbium(III) oxide in sulfuric acid:
The rod shaped "Form I" of the hydrogensulfate crystallizes from concentrated sulfuric acid at 250 °C. In diluted sulfuric acid, the brick shaped "Form II" crystallizes at 250 °C, while at 60 °C the mixed sulfate-hydrogensulfate is obtained.
The anhydrous compound cannot be prepared from solution but crystallizes from molten salt.