Structure
ZnS exists in two main crystalline forms, and this dualism is often a salient example of polymorphism. In both polymorphism, the coordination geometry at Zn and S are tetrahedral. The more stable cubic form is known also as zinc blende or sphalerite. The hexagonal form is known as the mineral wurtzite, although it also can be produced synthetically. The transition from the sphalerite form to the wurtzite form occurs at around 1020 celsius. A tetragonal form is also known as the very rare mineral called polhemusite, with the formula (Zn,Hg)S.
Read more about this topic: Zinc Sulfide
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