NdLa2(MnSi)6 crystallizes in the tetragonal I4/mmm space group. Nd(1) is bonded in a 16-coordinate geometry to eight equivalent Mn(1) and eight equivalent Si(1) atoms. La(1) is bonded in a 16-coordinate geometry to four equivalent Mn(1), four equivalent Mn(2), four equivalent Si(2), and four equivalent Si(3) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent Nd(1), two equivalent La(1), two equivalent Si(1), and two equivalent Si(3) atoms to form MnLa2Nd2Si4 tetrahedra that share corners with six equivalent Mn(1)La2Nd2Si4 tetrahedra, corners with six equivalent Mn(2)La4Si4 tetrahedra,  an edgeedge with one Mn(2)La4Si4 tetrahedra, edges with five equivalent Mn(1)La2Nd2Si4 tetrahedra, and faces with four equivalent Mn(1)La2Nd2Si4 tetrahedra. In the second Mn site, Mn(2) is bonded to four equivalent La(1) and four equivalent Si(2) atoms to form MnLa4Si4 tetrahedra that share corners with twelve equivalent Mn(1)La2Nd2Si4 tetrahedra, edges with two equivalent Mn(1)La2Nd2Si4 tetrahedra, edges with four equivalent Mn(2)La4Si4 tetrahedra, and faces with four equivalent Mn(2)La4Si4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent Nd(1), four equivalent Mn(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent La(1), four equivalent Mn(2), and one Si(3) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent La(1), four equivalent Mn(1), and one Si(2) atom.
NdLa2(MnSi)6 crystallizes in the tetragonal I4/mmm space group. Nd(1) is bonded in a 16-coordinate geometry to eight equivalent Mn(1) and eight equivalent Si(1) atoms. All Nd(1)-Mn(1) bond lengths are 3.31 Å. All Nd(1)-Si(1) bond lengths are 3.12 Å. La(1) is bonded in a 16-coordinate geometry to four equivalent Mn(1), four equivalent Mn(2), four equivalent Si(2), and four equivalent Si(3) atoms. All La(1)-Mn(1) bond lengths are 3.33 Å. All La(1)-Mn(2) bond lengths are 3.33 Å. All La(1)-Si(2) bond lengths are 3.14 Å. All La(1)-Si(3) bond lengths are 3.13 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent Nd(1), two equivalent La(1), two equivalent Si(1), and two equivalent Si(3) atoms to form MnLa2Nd2Si4 tetrahedra that share corners with six equivalent Mn(1)La2Nd2Si4 tetrahedra, corners with six equivalent Mn(2)La4Si4 tetrahedra,  an edgeedge with one Mn(2)La4Si4 tetrahedra, edges with five equivalent Mn(1)La2Nd2Si4 tetrahedra, and faces with four equivalent Mn(1)La2Nd2Si4 tetrahedra. Both Mn(1)-Si(1) bond lengths are 2.39 Å. Both Mn(1)-Si(3) bond lengths are 2.39 Å. In the second Mn site, Mn(2) is bonded to four equivalent La(1) and four equivalent Si(2) atoms to form MnLa4Si4 tetrahedra that share corners with twelve equivalent Mn(1)La2Nd2Si4 tetrahedra, edges with two equivalent Mn(1)La2Nd2Si4 tetrahedra, edges with four equivalent Mn(2)La4Si4 tetrahedra, and faces with four equivalent Mn(2)La4Si4 tetrahedra. All Mn(2)-Si(2) bond lengths are 2.38 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent Nd(1), four equivalent Mn(1), and one Si(1) atom. The Si(1)-Si(1) bond length is 2.65 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent La(1), four equivalent Mn(2), and one Si(3) atom. The Si(2)-Si(3) bond length is 2.72 Å. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent La(1), four equivalent Mn(1), and one Si(2) atom.