Nd2Si3 crystallizes in the hexagonal P-6m2 space group. Nd(1) is bonded in a 9-coordinate geometry to three equivalent Si(1), three equivalent Si(2), and three equivalent Si(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to six equivalent Nd(1) and three equivalent Si(3) atoms. In the second Si site, Si(2) is bonded to six equivalent Nd(1) atoms to form distorted edge-sharing SiNd6 pentagonal pyramids. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to six equivalent Nd(1) and three equivalent Si(1) atoms.
Nd2Si3 crystallizes in the hexagonal P-6m2 space group. Nd(1) is bonded in a 9-coordinate geometry to three equivalent Si(1), three equivalent Si(2), and three equivalent Si(3) atoms. All Nd(1)-Si(1) bond lengths are 3.14 Å. All Nd(1)-Si(2) bond lengths are 3.10 Å. All Nd(1)-Si(3) bond lengths are 3.14 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to six equivalent Nd(1) and three equivalent Si(3) atoms. All Si(1)-Si(3) bond lengths are 2.34 Å. In the second Si site, Si(2) is bonded to six equivalent Nd(1) atoms to form distorted edge-sharing SiNd6 pentagonal pyramids. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to six equivalent Nd(1) and three equivalent Si(1) atoms.