DyNi4Si is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the orthorhombic Cmmm space group. Dy(1) is bonded in a 18-coordinate geometry to six equivalent Ni(1), eight equivalent Ni(2), and four equivalent Si(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to three equivalent Dy(1), three equivalent Ni(1), four equivalent Ni(2), and two equivalent Si(1) atoms. In the second Ni site, Ni(2) is bonded to four equivalent Dy(1), two equivalent Ni(2), four equivalent Ni(1), and two equivalent Si(1) atoms to form NiDy4Si2Ni6 cuboctahedra that share corners with four equivalent Si(1)Dy4Ni8 cuboctahedra, corners with twelve equivalent Ni(2)Dy4Si2Ni6 cuboctahedra, edges with four equivalent Si(1)Dy4Ni8 cuboctahedra, edges with six equivalent Ni(2)Dy4Si2Ni6 cuboctahedra, faces with four equivalent Si(1)Dy4Ni8 cuboctahedra, and faces with six equivalent Ni(2)Dy4Si2Ni6 cuboctahedra. Si(1) is bonded to four equivalent Dy(1), four equivalent Ni(1), and four equivalent Ni(2) atoms to form distorted SiDy4Ni8 cuboctahedra that share corners with eight equivalent Ni(2)Dy4Si2Ni6 cuboctahedra, corners with eight equivalent Si(1)Dy4Ni8 cuboctahedra, edges with two equivalent Si(1)Dy4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Dy4Si2Ni6 cuboctahedra, faces with two equivalent Si(1)Dy4Ni8 cuboctahedra, and faces with eight equivalent Ni(2)Dy4Si2Ni6 cuboctahedra.
DyNi4Si is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the orthorhombic Cmmm space group. Dy(1) is bonded in a 18-coordinate geometry to six equivalent Ni(1), eight equivalent Ni(2), and four equivalent Si(1) atoms. There are two shorter (2.76 Å) and four longer (2.82 Å) Dy(1)-Ni(1) bond lengths. All Dy(1)-Ni(2) bond lengths are 3.08 Å. All Dy(1)-Si(1) bond lengths are 3.18 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to three equivalent Dy(1), three equivalent Ni(1), four equivalent Ni(2), and two equivalent Si(1) atoms. There is one shorter (2.57 Å) and two longer (2.91 Å) Ni(1)-Ni(1) bond lengths. All Ni(1)-Ni(2) bond lengths are 2.44 Å. Both Ni(1)-Si(1) bond lengths are 2.34 Å. In the second Ni site, Ni(2) is bonded to four equivalent Dy(1), two equivalent Ni(2), four equivalent Ni(1), and two equivalent Si(1) atoms to form NiDy4Si2Ni6 cuboctahedra that share corners with four equivalent Si(1)Dy4Ni8 cuboctahedra, corners with twelve equivalent Ni(2)Dy4Si2Ni6 cuboctahedra, edges with four equivalent Si(1)Dy4Ni8 cuboctahedra, edges with six equivalent Ni(2)Dy4Si2Ni6 cuboctahedra, faces with four equivalent Si(1)Dy4Ni8 cuboctahedra, and faces with six equivalent Ni(2)Dy4Si2Ni6 cuboctahedra. Both Ni(2)-Ni(2) bond lengths are 2.50 Å. Both Ni(2)-Si(1) bond lengths are 2.38 Å. Si(1) is bonded to four equivalent Dy(1), four equivalent Ni(1), and four equivalent Ni(2) atoms to form distorted SiDy4Ni8 cuboctahedra that share corners with eight equivalent Ni(2)Dy4Si2Ni6 cuboctahedra, corners with eight equivalent Si(1)Dy4Ni8 cuboctahedra, edges with two equivalent Si(1)Dy4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Dy4Si2Ni6 cuboctahedra, faces with two equivalent Si(1)Dy4Ni8 cuboctahedra, and faces with eight equivalent Ni(2)Dy4Si2Ni6 cuboctahedra.