Dy2PdSi3 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded to four equivalent Pd(1) and eight equivalent Si(1) atoms to form distorted DySi8Pd4 cuboctahedra that share edges with four equivalent Dy(2)Si12 cuboctahedra, edges with eight equivalent Dy(1)Si8Pd4 cuboctahedra, faces with two equivalent Dy(2)Si12 cuboctahedra, and faces with six equivalent Dy(1)Si8Pd4 cuboctahedra. In the second Dy site, Dy(2) is bonded to twelve equivalent Si(1) atoms to form DySi12 cuboctahedra that share edges with twelve equivalent Dy(1)Si8Pd4 cuboctahedra, faces with two equivalent Dy(2)Si12 cuboctahedra, and faces with six equivalent Dy(1)Si8Pd4 cuboctahedra. Pd(1) is bonded in a 9-coordinate geometry to six equivalent Dy(1) and three equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Dy(2), four equivalent Dy(1), one Pd(1), and two equivalent Si(1) atoms.
Dy2PdSi3 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded to four equivalent Pd(1) and eight equivalent Si(1) atoms to form distorted DySi8Pd4 cuboctahedra that share edges with four equivalent Dy(2)Si12 cuboctahedra, edges with eight equivalent Dy(1)Si8Pd4 cuboctahedra, faces with two equivalent Dy(2)Si12 cuboctahedra, and faces with six equivalent Dy(1)Si8Pd4 cuboctahedra. There are two shorter (3.01 Å) and two longer (3.20 Å) Dy(1)-Pd(1) bond lengths. There are four shorter (3.04 Å) and four longer (3.15 Å) Dy(1)-Si(1) bond lengths. In the second Dy site, Dy(2) is bonded to twelve equivalent Si(1) atoms to form DySi12 cuboctahedra that share edges with twelve equivalent Dy(1)Si8Pd4 cuboctahedra, faces with two equivalent Dy(2)Si12 cuboctahedra, and faces with six equivalent Dy(1)Si8Pd4 cuboctahedra. There are six shorter (3.06 Å) and six longer (3.08 Å) Dy(2)-Si(1) bond lengths. Pd(1) is bonded in a 9-coordinate geometry to six equivalent Dy(1) and three equivalent Si(1) atoms. All Pd(1)-Si(1) bond lengths are 2.41 Å. Si(1) is bonded in a 9-coordinate geometry to two equivalent Dy(2), four equivalent Dy(1), one Pd(1), and two equivalent Si(1) atoms. Both Si(1)-Si(1) bond lengths are 2.36 Å.