Zinc arsenide

Zinc arsenide is a binary compound of zinc with arsenic which forms gray tetragonal crystals. It is an inorganic semiconductor with a band gap of 1.0 eV.

Synthesis and reactions

Zinc arsenide can be prepared by the reaction of zinc with arsenic

Zn₃As₂ has a room-temperature tetragonal form that converts to a different tetragonal phase at 190 °C and to a third phase at 651 °C. In the room-temperature form, the zinc atoms are tetrahedrally coordinated and the arsenic atoms are surrounded by six zinc atoms at the vertices of a distorted cube. The crystalline structure of zinc arsenide is very similar to that of cadmium arsenide, zinc phosphide and cadmium phosphide. These compounds of the Zn-Cd-P-As quaternary system exhibit full continuous solid-solution.

Its lowest direct and indirect bandgaps are within 30 meV of each other.