Hf2(Ni7B2)3 crystallizes in the cubic Fm-3m space group. Hf(1) is bonded to four equivalent Ni(2) and twelve equivalent Ni(3) atoms to form distorted HfNi16 tetrahedra that share edges with six equivalent Hf(1)Ni16 tetrahedra and faces with four equivalent Ni(1)Ni12 cuboctahedra. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to twelve equivalent Ni(3) atoms to form NiNi12 cuboctahedra that share faces with eight equivalent Hf(1)Ni16 tetrahedra. In the second Ni site, Ni(2) is bonded to one Hf(1) and three equivalent B(1) atoms to form a mixture of distorted edge and corner-sharing NiHfB3 tetrahedra. In the third Ni site, Ni(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Hf(1), one Ni(1), and two equivalent B(1) atoms. B(1) is bonded in a 8-coordinate geometry to four equivalent Ni(2) and four equivalent Ni(3) atoms.
Hf2(Ni7B2)3 crystallizes in the cubic Fm-3m space group. Hf(1) is bonded to four equivalent Ni(2) and twelve equivalent Ni(3) atoms to form distorted HfNi16 tetrahedra that share edges with six equivalent Hf(1)Ni16 tetrahedra and faces with four equivalent Ni(1)Ni12 cuboctahedra. All Hf(1)-Ni(2) bond lengths are 2.49 Å. All Hf(1)-Ni(3) bond lengths are 2.90 Å. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to twelve equivalent Ni(3) atoms to form NiNi12 cuboctahedra that share faces with eight equivalent Hf(1)Ni16 tetrahedra. All Ni(1)-Ni(3) bond lengths are 2.54 Å. In the second Ni site, Ni(2) is bonded to one Hf(1) and three equivalent B(1) atoms to form a mixture of distorted edge and corner-sharing NiHfB3 tetrahedra. All Ni(2)-B(1) bond lengths are 2.12 Å. In the third Ni site, Ni(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Hf(1), one Ni(1), and two equivalent B(1) atoms. Both Ni(3)-B(1) bond lengths are 2.07 Å. B(1) is bonded in a 8-coordinate geometry to four equivalent Ni(2) and four equivalent Ni(3) atoms.