[2] Niobium(IV) iodide is a grey solid that reacts with water.

[1] Niobium(IV) iodide is an orthorhombic crystal with space group Cmc21 (No.

[3] Its crystal is formed by NbI6 octahedra connected by edges and also contains Nb-Nb bonds.

At 348 to 417 °C, the crystal structure of niobium(IV) iodide changes.

[4] Niobium(IV) iodide turns into a metal under extremely high pressure.