Mn2(Ni7B2)3 crystallizes in the cubic Fm-3m space group. Mn(1) is bonded in a distorted tetrahedral geometry to four equivalent Ni(2) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a cuboctahedral geometry to twelve equivalent Ni(3) atoms. In the second Ni site, Ni(2) is bonded to one Mn(1) and three equivalent B(1) atoms to form a mixture of edge and corner-sharing NiMnB3 tetrahedra. In the third Ni site, Ni(3) is bonded in a distorted bent 150 degrees geometry to 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.
Mn2(Ni7B2)3 crystallizes in the cubic Fm-3m space group. Mn(1) is bonded in a distorted tetrahedral geometry to four equivalent Ni(2) atoms. All Mn(1)-Ni(2) bond lengths are 2.36 Å. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a cuboctahedral geometry to twelve equivalent Ni(3) atoms. All Ni(1)-Ni(3) bond lengths are 2.50 Å. In the second Ni site, Ni(2) is bonded to one Mn(1) and three equivalent B(1) atoms to form a mixture of edge and corner-sharing NiMnB3 tetrahedra. All Ni(2)-B(1) bond lengths are 2.10 Å. In the third Ni site, Ni(3) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and two equivalent B(1) atoms. Both Ni(3)-B(1) bond lengths are 2.05 Å. B(1) is bonded in a 8-coordinate geometry to four equivalent Ni(2) and four equivalent Ni(3) atoms.