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Terbium (III) sulfate - is a salt of the rare earth metal terbium with sulfuric acid . It forms as octahydrate colorless crystals under excitation by short-wave UV radiation fluoresce green.
T 1172 (OTTO) Terbium(III) sulphate, octahydrate, 99.9% Cas 13842-67-6 - used in special lasers and as a dopant in solid-state devices.