Holmium acetate


Holmium acetate is the acetate salt of holmium, with a chemical formula of Ho3 as well as at least one hydrate.

Preparation

Holmium acetate can be obtained by dissolving holmium oxide in hot acetic acid
Dissolving holmium oxide in acetic acid at a pH of 4 will form the tetrahydrate of holmium acetate : The anhydrous material can be obtained by heating the hydrated acetate in acetic acid.

Physical properties and structure

Holmium acetate hemihepthydate decomposes at 105 °C, forming into a hemihydrate, further decomposing at 135 °C into an anhydride. Further adding heat will form Ho2, HoO then Ho2O2CO3, forming holmium oxide at 590 °C.
According to X-ray crystallography, anhydrous holmium acetate is a coordination polymer. Each Ho center is nine-coordinate, with two bidentate acetate ligands and the remaining sites occupied by oxygens provided by bridging acetate ligands. The lanthanum and praseodymium compounds are isostructural. In a second polymorph, holmium acetate has 8-coordination. A tetrahydrate has also been crystallized.

Applications

Holmium acetate is used in the manufacture of ceramics, glass, phosphors, metal halide lamps, and as a dopant in garnet lasers. It is also used in nuclear reactors to keep the chain reaction in check.