LuNi5Si3 crystallizes in the orthorhombic Pnma space group. Lu(1) is bonded in a 17-coordinate geometry to one Ni(3), one Ni(5), three equivalent Ni(1), three equivalent Ni(2), three equivalent Ni(4), two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. There are five inequivalent Ni sites. In the first Ni site, Ni(5) is bonded in a 5-coordinate geometry to one Lu(1), one Ni(2), one Ni(3), two equivalent Ni(1), two equivalent Ni(4), one Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. In the second Ni site, Ni(1) is bonded in a 12-coordinate geometry to three equivalent Lu(1), two equivalent Ni(5), three equivalent Ni(4), one Si(2), and three equivalent Si(1) atoms. In the third Ni site, Ni(2) is bonded to three equivalent Lu(1), one Ni(5), two equivalent Ni(2), two equivalent Ni(3), one Si(3), and three equivalent Si(2) atoms to form distorted face-sharing NiLu3Si4Ni5 cuboctahedra. In the fourth Ni site, Ni(3) is bonded in a 10-coordinate geometry to one Lu(1), one Ni(5), two equivalent Ni(2), two equivalent Ni(3), one Si(2), and three equivalent Si(3) atoms. In the fifth Ni site, Ni(4) is bonded in a 12-coordinate geometry to three equivalent Lu(1), two equivalent Ni(5), three equivalent Ni(1), one Si(3), and three equivalent Si(1) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Lu(1), one Ni(5), three equivalent Ni(1), and three equivalent Ni(4) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Lu(1), one Ni(1), one Ni(3), two equivalent Ni(5), and three equivalent Ni(2) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Lu(1), one Ni(2), one Ni(4), two equivalent Ni(5), and three equivalent Ni(3) atoms.
LuNi5Si3 crystallizes in the orthorhombic Pnma space group. Lu(1) is bonded in a 17-coordinate geometry to one Ni(3), one Ni(5), three equivalent Ni(1), three equivalent Ni(2), three equivalent Ni(4), two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. The Lu(1)-Ni(3) bond length is 2.96 Å. The Lu(1)-Ni(5) bond length is 3.24 Å. There are two shorter (2.95 Å) and one longer (3.17 Å) Lu(1)-Ni(1) bond length. There are two shorter (3.17 Å) and one longer (3.23 Å) Lu(1)-Ni(2) bond length. There are two shorter (3.00 Å) and one longer (3.06 Å) Lu(1)-Ni(4) bond length. Both Lu(1)-Si(1) bond lengths are 2.87 Å. Both Lu(1)-Si(2) bond lengths are 2.89 Å. Both Lu(1)-Si(3) bond lengths are 2.88 Å. There are five inequivalent Ni sites. In the first Ni site, Ni(5) is bonded in a 5-coordinate geometry to one Lu(1), one Ni(2), one Ni(3), two equivalent Ni(1), two equivalent Ni(4), one Si(1), two equivalent Si(2), and two equivalent Si(3) atoms. The Ni(5)-Ni(2) bond length is 2.68 Å. The Ni(5)-Ni(3) bond length is 2.55 Å. Both Ni(5)-Ni(1) bond lengths are 2.71 Å. Both Ni(5)-Ni(4) bond lengths are 2.89 Å. The Ni(5)-Si(1) bond length is 2.30 Å. Both Ni(5)-Si(2) bond lengths are 2.42 Å. Both Ni(5)-Si(3) bond lengths are 2.48 Å. In the second Ni site, Ni(1) is bonded in a 12-coordinate geometry to three equivalent Lu(1), two equivalent Ni(5), three equivalent Ni(4), one Si(2), and three equivalent Si(1) atoms. There is one shorter (2.59 Å) and two longer (2.66 Å) Ni(1)-Ni(4) bond lengths. The Ni(1)-Si(2) bond length is 2.31 Å. There is one shorter (2.33 Å) and two longer (2.38 Å) Ni(1)-Si(1) bond lengths. In the third Ni site, Ni(2) is bonded to three equivalent Lu(1), one Ni(5), two equivalent Ni(2), two equivalent Ni(3), one Si(3), and three equivalent Si(2) atoms to form distorted face-sharing NiLu3Si4Ni5 cuboctahedra. Both Ni(2)-Ni(2) bond lengths are 2.56 Å. Both Ni(2)-Ni(3) bond lengths are 2.51 Å. The Ni(2)-Si(3) bond length is 2.38 Å. There is one shorter (2.29 Å) and two longer (2.40 Å) Ni(2)-Si(2) bond lengths. In the fourth Ni site, Ni(3) is bonded in a 10-coordinate geometry to one Lu(1), one Ni(5), two equivalent Ni(2), two equivalent Ni(3), one Si(2), and three equivalent Si(3) atoms. Both Ni(3)-Ni(3) bond lengths are 2.50 Å. The Ni(3)-Si(2) bond length is 2.25 Å. There is one shorter (2.29 Å) and two longer (2.30 Å) Ni(3)-Si(3) bond lengths. In the fifth Ni site, Ni(4) is bonded in a 12-coordinate geometry to three equivalent Lu(1), two equivalent Ni(5), three equivalent Ni(1), one Si(3), and three equivalent Si(1) atoms. The Ni(4)-Si(3) bond length is 2.24 Å. There is one shorter (2.29 Å) and two longer (2.34 Å) Ni(4)-Si(1) bond lengths. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Lu(1), one Ni(5), three equivalent Ni(1), and three equivalent Ni(4) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Lu(1), one Ni(1), one Ni(3), two equivalent Ni(5), and three equivalent Ni(2) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Lu(1), one Ni(2), one Ni(4), two equivalent Ni(5), and three equivalent Ni(3) atoms.