Ni3As crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ni1+ is bonded in a see-saw-like geometry to four equivalent As3- atoms. There are two shorter (2.52 Å) and two longer (2.55 Å) Ni–As bond lengths. As3- is bonded to twelve equivalent Ni1+ atoms to form a mixture of corner and face-sharing AsNi12 cuboctahedra.