NdFe6Bi(BO3)8 is Calcite-derived structured and crystallizes in the trigonal R32 space group. Nd(1) is bonded in a 6-coordinate geometry to six equivalent O(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Bi(1)O6 pentagonal pyramids and edges with two equivalent Fe(2)O6 octahedra. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form edge-sharing FeO6 octahedra. There are two inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to three equivalent O(4) atoms. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. Bi(1) is bonded to six equivalent O(3) atoms to form distorted BiO6 pentagonal pyramids that share corners with six equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 60°. There are four inequivalent O sites. In the first O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one B(1) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one B(2) atom. In the third O site, O(2) is bonded in a 3-coordinate geometry to one Nd(1), one Fe(2), and one B(2) atom. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one Fe(1), one B(2), and one Bi(1) atom.
NdFe6Bi(BO3)8 is Calcite-derived structured and crystallizes in the trigonal R32 space group. Nd(1) is bonded in a 6-coordinate geometry to six equivalent O(2) atoms. All Nd(1)-O(2) bond lengths are 2.41 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Bi(1)O6 pentagonal pyramids and edges with two equivalent Fe(2)O6 octahedra. Both Fe(1)-O(1) bond lengths are 2.00 Å. Both Fe(1)-O(3) bond lengths are 1.95 Å. Both Fe(1)-O(4) bond lengths are 1.99 Å. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form edge-sharing FeO6 octahedra. Both Fe(2)-O(1) bond lengths are 2.07 Å. Both Fe(2)-O(2) bond lengths are 1.98 Å. Both Fe(2)-O(4) bond lengths are 2.06 Å. There are two inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to three equivalent O(4) atoms. All B(1)-O(4) bond lengths are 1.39 Å. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. The B(2)-O(1) bond length is 1.39 Å. The B(2)-O(2) bond length is 1.38 Å. The B(2)-O(3) bond length is 1.38 Å. Bi(1) is bonded to six equivalent O(3) atoms to form distorted BiO6 pentagonal pyramids that share corners with six equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 60°. All Bi(1)-O(3) bond lengths are 2.42 Å. There are four inequivalent O sites. In the first O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one B(1) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one B(2) atom. In the third O site, O(2) is bonded in a 3-coordinate geometry to one Nd(1), one Fe(2), and one B(2) atom. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one Fe(1), one B(2), and one Bi(1) atom.