In chemistry an antimonate is a compound which contains a metallic element, oxygen, and antimony in an oxidation state of +5. These compounds adopt polymeric structures with M-O-Sb linkages. They can be considered to be derivatives of the hypothetical antimonic acid , or combinations of metal oxides and antimony pentoxide, .

Historically these compounds were assumed to be analogous to the phosphates and formulas such as and were used and the compounds described as hydrated meta-antimonates and pyro-antimonates. It is now known that is actually , containing the anion, and that is actually .

Nomenclature

IUPAC recommendations are that compounds with anions containing antimony(V) have the antimonate(V) suffix or antimonate followed by a charge number, for example the ion would be called hexahydridoxidoantimonate(V) or alternatively hexahydroxidoantimonate(1−).

Examples

Some examples of antimonates and their structures are shown below:

• has a superstructure with isolated units.

• Sodium antimonate, , has the ilmenite structure, with hexagonal close packed oxide ions with each ion, and occupying a third of the octahedral sites.

• has the trirutile structure, which is similar to the rutile structure except that there are two different cations in the lattice.

• has the rutile structure with random occupancy.

• Lead antimonate, , Naples yellow, has the pyrochlore structure.

• Calcium antimonate, , has the weberite structure.

• Ferric ortho-antimonate, or , has the rutile structure with random occupancy.

See also

• Antimonate mineral

• Antimonide

• Antimonite

References