Dy2Ni3Si5 crystallizes in the orthorhombic Ibam space group. Dy(1) is bonded in a 16-coordinate geometry to two equivalent Ni(2), four equivalent Ni(1), two equivalent Si(1), four equivalent Si(2), and four equivalent Si(3) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 9-coordinate geometry to four equivalent Dy(1), one Si(3), two equivalent Si(1), and two equivalent Si(2) atoms. In the second Ni site, Ni(2) is bonded in a 12-coordinate geometry to four equivalent Dy(1), two equivalent Ni(2), two equivalent Si(2), and four equivalent Si(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to four equivalent Dy(1) and four equivalent Ni(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent Dy(1), one Ni(2), two equivalent Ni(1), and two equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Dy(1), one Ni(1), two equivalent Ni(2), and two equivalent Si(2) atoms.
Dy2Ni3Si5 crystallizes in the orthorhombic Ibam space group. Dy(1) is bonded in a 16-coordinate geometry to two equivalent Ni(2), four equivalent Ni(1), two equivalent Si(1), four equivalent Si(2), and four equivalent Si(3) atoms. Both Dy(1)-Ni(2) bond lengths are 3.22 Å. There are a spread of Dy(1)-Ni(1) bond distances ranging from 2.97-3.15 Å. Both Dy(1)-Si(1) bond lengths are 3.02 Å. There are two shorter (3.04 Å) and two longer (3.10 Å) Dy(1)-Si(2) bond lengths. There are a spread of Dy(1)-Si(3) bond distances ranging from 2.85-3.03 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 9-coordinate geometry to four equivalent Dy(1), one Si(3), two equivalent Si(1), and two equivalent Si(2) atoms. The Ni(1)-Si(3) bond length is 2.26 Å. Both Ni(1)-Si(1) bond lengths are 2.31 Å. Both Ni(1)-Si(2) bond lengths are 2.29 Å. In the second Ni site, Ni(2) is bonded in a 12-coordinate geometry to four equivalent Dy(1), two equivalent Ni(2), two equivalent Si(2), and four equivalent Si(3) atoms. Both Ni(2)-Ni(2) bond lengths are 2.82 Å. Both Ni(2)-Si(2) bond lengths are 2.59 Å. All Ni(2)-Si(3) bond lengths are 2.34 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to four equivalent Dy(1) and four equivalent Ni(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent Dy(1), one Ni(2), two equivalent Ni(1), and two equivalent Si(3) atoms. Both Si(2)-Si(3) bond lengths are 2.45 Å. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Dy(1), one Ni(1), two equivalent Ni(2), and two equivalent Si(2) atoms.