This dark violet-blue compound exists as volatile crystals under standard conditions.

It is an important starting reagent in the preparation of tungsten compounds.

The wine-red β can be obtained by rapid cooling, whereas the blue α form is more stable at room temperature.

Both polymorphs feature WCl6 molecules that have octahedral geometry, in which all six W–Cl bonds are equivalent, and their length is equal to 224–226 pm.

[6][7] WCl6 is an aggressively corrosive oxidant, and hydrolyzes to release hydrogen chloride.