Ni21Zn2B20 crystallizes in the tetragonal I4/mmm space group. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 7-coordinate geometry to one Zn(1), two equivalent B(1), two equivalent B(2), and two equivalent B(3) atoms. In the second Ni site, Ni(2) is bonded in a 8-coordinate geometry to two equivalent B(1), two equivalent B(3), and four equivalent B(2) atoms. In the third Ni site, Ni(3) is bonded in a 8-coordinate geometry to two equivalent Zn(1), two equivalent B(2), and four equivalent B(1) atoms. In the fourth Ni site, Ni(4) is bonded in a 4-coordinate geometry to four equivalent B(1) atoms. In the fifth Ni site, Ni(5) is bonded in a distorted square co-planar geometry to two equivalent Zn(1) and four equivalent B(3) atoms. In the sixth Ni site, Ni(6) is bonded in a 9-coordinate geometry to one Zn(1), four equivalent B(1), and four equivalent B(2) atoms. Zn(1) is bonded in a 10-coordinate geometry to one Ni(5), one Ni(6), four equivalent Ni(1), and four equivalent Ni(3) atoms. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to one Ni(2), one Ni(4), one Ni(6), two equivalent Ni(1), two equivalent Ni(3), and two equivalent B(2) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to one Ni(3), one Ni(6), two equivalent Ni(1), two equivalent Ni(2), one B(3), and two equivalent B(1) atoms. In the third B site, B(3) is bonded in a 9-coordinate geometry to one Ni(5), two equivalent Ni(2), four equivalent Ni(1), and two equivalent B(2) atoms.
Ni21Zn2B20 crystallizes in the tetragonal I4/mmm space group. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 7-coordinate geometry to one Zn(1), two equivalent B(1), two equivalent B(2), and two equivalent B(3) atoms. The Ni(1)-Zn(1) bond length is 2.50 Å. Both Ni(1)-B(1) bond lengths are 2.18 Å. Both Ni(1)-B(2) bond lengths are 2.12 Å. Both Ni(1)-B(3) bond lengths are 2.16 Å. In the second Ni site, Ni(2) is bonded in a 8-coordinate geometry to two equivalent B(1), two equivalent B(3), and four equivalent B(2) atoms. Both Ni(2)-B(1) bond lengths are 2.21 Å. Both Ni(2)-B(3) bond lengths are 2.15 Å. All Ni(2)-B(2) bond lengths are 2.15 Å. In the third Ni site, Ni(3) is bonded in a 8-coordinate geometry to two equivalent Zn(1), two equivalent B(2), and four equivalent B(1) atoms. Both Ni(3)-Zn(1) bond lengths are 2.68 Å. Both Ni(3)-B(2) bond lengths are 2.11 Å. All Ni(3)-B(1) bond lengths are 2.29 Å. In the fourth Ni site, Ni(4) is bonded in a 4-coordinate geometry to four equivalent B(1) atoms. All Ni(4)-B(1) bond lengths are 1.99 Å. In the fifth Ni site, Ni(5) is bonded in a distorted square co-planar geometry to two equivalent Zn(1) and four equivalent B(3) atoms. Both Ni(5)-Zn(1) bond lengths are 2.72 Å. All Ni(5)-B(3) bond lengths are 2.06 Å. In the sixth Ni site, Ni(6) is bonded in a 9-coordinate geometry to one Zn(1), four equivalent B(1), and four equivalent B(2) atoms. The Ni(6)-Zn(1) bond length is 2.44 Å. All Ni(6)-B(1) bond lengths are 2.16 Å. All Ni(6)-B(2) bond lengths are 2.14 Å. Zn(1) is bonded in a 10-coordinate geometry to one Ni(5), one Ni(6), four equivalent Ni(1), and four equivalent Ni(3) atoms. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to one Ni(2), one Ni(4), one Ni(6), two equivalent Ni(1), two equivalent Ni(3), and two equivalent B(2) atoms. Both B(1)-B(2) bond lengths are 1.76 Å. In the second B site, B(2) is bonded in a 9-coordinate geometry to one Ni(3), one Ni(6), two equivalent Ni(1), two equivalent Ni(2), one B(3), and two equivalent B(1) atoms. The B(2)-B(3) bond length is 1.77 Å. In the third B site, B(3) is bonded in a 9-coordinate geometry to one Ni(5), two equivalent Ni(2), four equivalent Ni(1), and two equivalent B(2) atoms.