Ca5Ni15B4 crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a distorted hexagonal planar geometry to three equivalent Ni(2) and three equivalent Ni(3) atoms. In the second Ca site, Ca(2) is bonded in a 12-coordinate geometry to three equivalent Ni(5) and nine equivalent Ni(4) atoms. In the third Ca site, Ca(3) is bonded in a 18-coordinate geometry to six equivalent Ni(1), six equivalent Ni(4), three equivalent B(1), and three equivalent B(2) atoms. There are five inequivalent Ni sites. In the first Ni site, Ni(5) is bonded to six equivalent Ca(2) and six equivalent Ni(4) atoms to form edge-sharing NiCa6Ni6 cuboctahedra. In the second Ni site, Ni(1) is bonded in a distorted L-shaped geometry to two equivalent Ca(3), one Ni(2), one Ni(3), one B(1), and one B(2) atom. In the third Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Ca(1) and six equivalent Ni(1) atoms. In the fourth Ni site, Ni(3) is bonded in a 9-coordinate geometry to three equivalent Ca(1) and six equivalent Ni(1) atoms. In the fifth Ni site, Ni(4) is bonded in a distorted L-shaped geometry to two equivalent Ca(3), three equivalent Ca(2), one Ni(5), one B(1), and one B(2) atom. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 6-coordinate geometry to three equivalent Ca(3), three equivalent Ni(1), and three equivalent Ni(4) atoms. In the second B site, B(2) is bonded in a 6-coordinate geometry to three equivalent Ca(3), three equivalent Ni(1), and three equivalent Ni(4) atoms.
Ca5Ni15B4 crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a distorted hexagonal planar geometry to three equivalent Ni(2) and three equivalent Ni(3) atoms. All Ca(1)-Ni(2) bond lengths are 2.94 Å. All Ca(1)-Ni(3) bond lengths are 2.94 Å. In the second Ca site, Ca(2) is bonded in a 12-coordinate geometry to three equivalent Ni(5) and nine equivalent Ni(4) atoms. All Ca(2)-Ni(5) bond lengths are 2.98 Å. There are six shorter (3.03 Å) and three longer (3.07 Å) Ca(2)-Ni(4) bond lengths. In the third Ca site, Ca(3) is bonded in a 18-coordinate geometry to six equivalent Ni(1), six equivalent Ni(4), three equivalent B(1), and three equivalent B(2) atoms. All Ca(3)-Ni(1) bond lengths are 2.85 Å. All Ca(3)-Ni(4) bond lengths are 2.95 Å. All Ca(3)-B(1) bond lengths are 2.94 Å. All Ca(3)-B(2) bond lengths are 2.94 Å. There are five inequivalent Ni sites. In the first Ni site, Ni(5) is bonded to six equivalent Ca(2) and six equivalent Ni(4) atoms to form edge-sharing NiCa6Ni6 cuboctahedra. All Ni(5)-Ni(4) bond lengths are 2.61 Å. In the second Ni site, Ni(1) is bonded in a distorted L-shaped geometry to two equivalent Ca(3), one Ni(2), one Ni(3), one B(1), and one B(2) atom. The Ni(1)-Ni(2) bond length is 2.49 Å. The Ni(1)-Ni(3) bond length is 2.50 Å. The Ni(1)-B(1) bond length is 2.01 Å. The Ni(1)-B(2) bond length is 2.04 Å. In the third Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Ca(1) and six equivalent Ni(1) atoms. In the fourth Ni site, Ni(3) is bonded in a 9-coordinate geometry to three equivalent Ca(1) and six equivalent Ni(1) atoms. In the fifth Ni site, Ni(4) is bonded in a distorted L-shaped geometry to two equivalent Ca(3), three equivalent Ca(2), one Ni(5), one B(1), and one B(2) atom. The Ni(4)-B(1) bond length is 2.01 Å. The Ni(4)-B(2) bond length is 2.02 Å. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 6-coordinate geometry to three equivalent Ca(3), three equivalent Ni(1), and three equivalent Ni(4) atoms. In the second B site, B(2) is bonded in a 6-coordinate geometry to three equivalent Ca(3), three equivalent Ni(1), and three equivalent Ni(4) atoms.