Na3Nd5Cl18 crystallizes in the hexagonal P-6 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 9-coordinate geometry to three equivalent Cl(4) and six equivalent Cl(2) atoms. In the second Na site, Na(2) is bonded in a distorted trigonal planar geometry to three equivalent Cl(2) and three equivalent Cl(4) atoms. There are three inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 9-coordinate geometry to three equivalent Cl(1), three equivalent Cl(2), and three equivalent Cl(3) atoms. In the second Nd site, Nd(2) is bonded in a 9-coordinate geometry to three equivalent Cl(1) and six equivalent Cl(3) atoms. In the third Nd site, Nd(3) is bonded in a 9-coordinate geometry to three equivalent Cl(2), three equivalent Cl(3), and three equivalent Cl(4) atoms. There are four inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a trigonal non-coplanar geometry to one Nd(2) and two equivalent Nd(1) atoms. In the second Cl site, Cl(2) is bonded to one Na(1), one Na(2), one Nd(1), and one Nd(3) atom to form a mixture of edge and corner-sharing ClNa2Nd2 tetrahedra. In the third Cl site, Cl(3) is bonded in a distorted trigonal non-coplanar geometry to one Nd(1), one Nd(2), and one Nd(3) atom. In the fourth Cl site, Cl(4) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), and two equivalent Nd(3) atoms.
Na3Nd5Cl18 crystallizes in the hexagonal P-6 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 9-coordinate geometry to three equivalent Cl(4) and six equivalent Cl(2) atoms. All Na(1)-Cl(4) bond lengths are 3.10 Å. All Na(1)-Cl(2) bond lengths are 2.96 Å. In the second Na site, Na(2) is bonded in a distorted trigonal planar geometry to three equivalent Cl(2) and three equivalent Cl(4) atoms. All Na(2)-Cl(2) bond lengths are 2.73 Å. All Na(2)-Cl(4) bond lengths are 3.36 Å. There are three inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 9-coordinate geometry to three equivalent Cl(1), three equivalent Cl(2), and three equivalent Cl(3) atoms. All Nd(1)-Cl(1) bond lengths are 2.90 Å. All Nd(1)-Cl(2) bond lengths are 2.85 Å. All Nd(1)-Cl(3) bond lengths are 3.00 Å. In the second Nd site, Nd(2) is bonded in a 9-coordinate geometry to three equivalent Cl(1) and six equivalent Cl(3) atoms. All Nd(2)-Cl(1) bond lengths are 2.97 Å. All Nd(2)-Cl(3) bond lengths are 2.89 Å. In the third Nd site, Nd(3) is bonded in a 9-coordinate geometry to three equivalent Cl(2), three equivalent Cl(3), and three equivalent Cl(4) atoms. All Nd(3)-Cl(2) bond lengths are 2.94 Å. All Nd(3)-Cl(3) bond lengths are 2.95 Å. All Nd(3)-Cl(4) bond lengths are 2.88 Å. There are four inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a trigonal non-coplanar geometry to one Nd(2) and two equivalent Nd(1) atoms. In the second Cl site, Cl(2) is bonded to one Na(1), one Na(2), one Nd(1), and one Nd(3) atom to form a mixture of edge and corner-sharing ClNa2Nd2 tetrahedra. In the third Cl site, Cl(3) is bonded in a distorted trigonal non-coplanar geometry to one Nd(1), one Nd(2), and one Nd(3) atom. In the fourth Cl site, Cl(4) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), and two equivalent Nd(3) atoms.