Tungsten(II) iodide


Tungsten iodide is an iodide of tungsten, with the chemical formula I4, or abbreviated as WI2.

Preparation

Tungsten diiodide can obtained from the decomposition from tungsten(III) iodide:
It can also be formed by the displacement reaction of tungsten(II) chloride and iodine:
It can also be formed by the direct reaction of tungsten and iodine, which is a reversible reaction. This reaction can be used in halogen lamps.
Tungsten iodide can also be obtained by reacting tungsten hexacarbonyl with iodine.

Properties

Tungsten iodide is a dark brown-colored solid that is stable in air and moisture. Its structure is the same as tungsten chloride, crystallising orthorhombic [crystal system], with space group Bbem, and lattice parameters a = 1258 pm, b = 1259 pm, c = 1584 pm.