Ni2Si is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ni sites. In the first Ni site, Ni(2) is bonded in a 13-coordinate geometry to two equivalent Ni(2), six equivalent Ni(1), and five equivalent Si(1) atoms. In the second Ni site, Ni(1) is bonded in a 13-coordinate geometry to two equivalent Ni(1), six equivalent Ni(2), and five equivalent Si(1) atoms. Si(1) is bonded in a 10-coordinate geometry to five equivalent Ni(1) and five equivalent Ni(2) atoms.
Ni2Si is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ni sites. In the first Ni site, Ni(2) is bonded in a 13-coordinate geometry to two equivalent Ni(2), six equivalent Ni(1), and five equivalent Si(1) atoms. Both Ni(2)-Ni(2) bond lengths are 2.64 Å. There are a spread of Ni(2)-Ni(1) bond distances ranging from 2.54-2.68 Å. There are a spread of Ni(2)-Si(1) bond distances ranging from 2.29-2.68 Å. In the second Ni site, Ni(1) is bonded in a 13-coordinate geometry to two equivalent Ni(1), six equivalent Ni(2), and five equivalent Si(1) atoms. Both Ni(1)-Ni(1) bond lengths are 2.54 Å. There are a spread of Ni(1)-Si(1) bond distances ranging from 2.32-2.55 Å. Si(1) is bonded in a 10-coordinate geometry to five equivalent Ni(1) and five equivalent Ni(2) atoms.