Niobium perchlorate

Niobium perchlorate is a chemical compound with the formula Nb(ClO4)5. It is a hygroscopic, white crystalline solid that readily reacts with moist air or water to produce niobium(V) oxide.

Synthesis and reactions
Niobium perchlorate is produced from the reaction of niobium pentachloride and anhydrous perchloric acid:
 * NbCl5 + 5 HClO4 → Nb(ClO4)5 + 5 HCl

It decomposes at 70 C to niobyl perchlorate, releasing dichlorine heptoxide:
 * Nb(ClO4)5 → NbO(ClO4)3 + Cl2O7

Niobyl perchlorate further decomposes at 115 C to NbO2ClO4, which decomposes at 220 C to niobium pentoxide.

Perchloratoniobates, such as Cs[Nb(ClO4)6] and Cs2[Nb(ClO4)7], are produced by the reaction of perchlorate sources, such as cesium perchlorate and niobium perchlorate, in anhydrous perchloric acid at 0 C.

Structure
Although the structure of niobium perchlorate has not been elucidated by single-crystal X-ray diffraction, the structure has been probed by IR spectroscopy and powder X-ray diffraction. Niobium perchlorate has both monodentate and bidentate perchlorate ligands.