Nd4Si5 crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 8-coordinate geometry to two equivalent Si(1), two equivalent Si(5), and four equivalent Si(4) atoms. In the second Nd site, Nd(2) is bonded in a 10-coordinate geometry to two equivalent Si(2), four equivalent Si(3), and four equivalent Si(5) atoms. In the third Nd site, Nd(3) is bonded in a 7-coordinate geometry to one Si(1), two equivalent Si(3), and four equivalent Si(2) atoms. In the fourth Nd site, Nd(4) is bonded in a 7-coordinate geometry to one Si(2), two equivalent Si(4), and four equivalent Si(1) atoms. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Nd(3), two equivalent Nd(1), four equivalent Nd(4), and two equivalent Si(4) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Nd(4), two equivalent Nd(2), four equivalent Nd(3), and two equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Nd(3), four equivalent Nd(2), one Si(5), and two equivalent Si(2) atoms. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to two equivalent Nd(4), four equivalent Nd(1), and two equivalent Si(1) atoms. In the fifth Si site, Si(5) is bonded in a 7-coordinate geometry to two equivalent Nd(1), four equivalent Nd(2), and one Si(3) atom.
Nd4Si5 crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 8-coordinate geometry to two equivalent Si(1), two equivalent Si(5), and four equivalent Si(4) atoms. Both Nd(1)-Si(1) bond lengths are 3.28 Å. Both Nd(1)-Si(5) bond lengths are 3.11 Å. All Nd(1)-Si(4) bond lengths are 3.10 Å. In the second Nd site, Nd(2) is bonded in a 10-coordinate geometry to two equivalent Si(2), four equivalent Si(3), and four equivalent Si(5) atoms. Both Nd(2)-Si(2) bond lengths are 3.28 Å. All Nd(2)-Si(3) bond lengths are 3.11 Å. All Nd(2)-Si(5) bond lengths are 3.18 Å. In the third Nd site, Nd(3) is bonded in a 7-coordinate geometry to one Si(1), two equivalent Si(3), and four equivalent Si(2) atoms. The Nd(3)-Si(1) bond length is 3.25 Å. Both Nd(3)-Si(3) bond lengths are 3.10 Å. All Nd(3)-Si(2) bond lengths are 3.03 Å. In the fourth Nd site, Nd(4) is bonded in a 7-coordinate geometry to one Si(2), two equivalent Si(4), and four equivalent Si(1) atoms. The Nd(4)-Si(2) bond length is 3.22 Å. Both Nd(4)-Si(4) bond lengths are 3.13 Å. All Nd(4)-Si(1) bond lengths are 3.04 Å. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Nd(3), two equivalent Nd(1), four equivalent Nd(4), and two equivalent Si(4) atoms. Both Si(1)-Si(4) bond lengths are 2.45 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Nd(4), two equivalent Nd(2), four equivalent Nd(3), and two equivalent Si(3) atoms. Both Si(2)-Si(3) bond lengths are 2.44 Å. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Nd(3), four equivalent Nd(2), one Si(5), and two equivalent Si(2) atoms. The Si(3)-Si(5) bond length is 2.33 Å. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to two equivalent Nd(4), four equivalent Nd(1), and two equivalent Si(1) atoms. In the fifth Si site, Si(5) is bonded in a 7-coordinate geometry to two equivalent Nd(1), four equivalent Nd(2), and one Si(3) atom.