Nd5Si3O13 crystallizes in the hexagonal P6_3 space group. There are three inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 7-coordinate geometry to one O(2), one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms. In the second Nd site, Nd(2) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(4) atoms. In the third Nd site, Nd(3) is bonded in a 9-coordinate geometry to three equivalent O(2), three equivalent O(3), and three equivalent O(4) atoms. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are five inequivalent O sites. In the first O site, O(4) is bonded in a 4-coordinate geometry to one Nd(1), one Nd(2), one Nd(3), and one Si(1) atom. In the second O site, O(5) is bonded in a trigonal planar geometry to three equivalent Nd(1) atoms. In the third O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Nd(1) and one Si(1) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Nd(1), one Nd(2), one Nd(3), and one Si(1) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Nd(3), two equivalent Nd(1), and one Si(1) atom.
Nd5Si3O13 crystallizes in the hexagonal P6_3 space group. There are three inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 7-coordinate geometry to one O(2), one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms. The Nd(1)-O(2) bond length is 2.50 Å. The Nd(1)-O(4) bond length is 2.72 Å. The Nd(1)-O(5) bond length is 2.30 Å. There is one shorter (2.41 Å) and one longer (2.49 Å) Nd(1)-O(1) bond length. There is one shorter (2.44 Å) and one longer (2.60 Å) Nd(1)-O(3) bond length. In the second Nd site, Nd(2) is bonded in a 6-coordinate geometry to three equivalent O(2) and three equivalent O(4) atoms. All Nd(2)-O(2) bond lengths are 2.50 Å. All Nd(2)-O(4) bond lengths are 2.42 Å. In the third Nd site, Nd(3) is bonded in a 9-coordinate geometry to three equivalent O(2), three equivalent O(3), and three equivalent O(4) atoms. All Nd(3)-O(2) bond lengths are 2.59 Å. All Nd(3)-O(3) bond lengths are 2.75 Å. All Nd(3)-O(4) bond lengths are 2.49 Å. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. The Si(1)-O(1) bond length is 1.65 Å. The Si(1)-O(2) bond length is 1.65 Å. The Si(1)-O(3) bond length is 1.65 Å. The Si(1)-O(4) bond length is 1.64 Å. There are five inequivalent O sites. In the first O site, O(4) is bonded in a 4-coordinate geometry to one Nd(1), one Nd(2), one Nd(3), and one Si(1) atom. In the second O site, O(5) is bonded in a trigonal planar geometry to three equivalent Nd(1) atoms. In the third O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Nd(1) and one Si(1) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Nd(1), one Nd(2), one Nd(3), and one Si(1) atom. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Nd(3), two equivalent Nd(1), and one Si(1) atom.