NaSrTbBiO6 crystallizes in the orthorhombic Pnnn space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a square co-planar geometry to four equivalent O(3) atoms. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(3) atoms. Tb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form TbO6 octahedra that share corners with six equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-31°. Bi(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form BiO6 octahedra that share corners with six equivalent Tb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-31°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Sr(2), one Tb(1), and one Bi(1) atom to form distorted OSr2TbBi trigonal pyramids that share corners with four equivalent O(2)NaSrTbBi tetrahedra, corners with six equivalent O(1)Sr2TbBi trigonal pyramids, edges with two equivalent O(2)NaSrTbBi tetrahedra, and  an edgeedge with one O(1)Sr2TbBi trigonal pyramid. In the second O site, O(2) is bonded to one Na(1), one Sr(1), one Tb(1), and one Bi(1) atom to form distorted ONaSrTbBi tetrahedra that share corners with six equivalent O(2)NaSrTbBi tetrahedra, corners with four equivalent O(1)Sr2TbBi trigonal pyramids,  an edgeedge with one O(2)NaSrTbBi tetrahedra, and edges with two equivalent O(1)Sr2TbBi trigonal pyramids. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Na(2), one Sr(2), one Tb(1), and one Bi(1) atom.
NaSrTbBiO6 crystallizes in the orthorhombic Pnnn space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(2) atoms. All Na(1)-O(2) bond lengths are 2.68 Å. In the second Na site, Na(2) is bonded in a square co-planar geometry to four equivalent O(3) atoms. All Na(2)-O(3) bond lengths are 2.44 Å. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. All Sr(1)-O(1) bond lengths are 2.78 Å. All Sr(1)-O(2) bond lengths are 2.64 Å. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(3) atoms. All Sr(2)-O(1) bond lengths are 2.62 Å. All Sr(2)-O(3) bond lengths are 2.90 Å. Tb(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form TbO6 octahedra that share corners with six equivalent Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-31°. Both Tb(1)-O(1) bond lengths are 2.24 Å. Both Tb(1)-O(2) bond lengths are 2.25 Å. Both Tb(1)-O(3) bond lengths are 2.28 Å. Bi(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form BiO6 octahedra that share corners with six equivalent Tb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-31°. Both Bi(1)-O(1) bond lengths are 2.13 Å. Both Bi(1)-O(2) bond lengths are 2.12 Å. Both Bi(1)-O(3) bond lengths are 2.13 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Sr(2), one Tb(1), and one Bi(1) atom to form distorted OSr2TbBi trigonal pyramids that share corners with four equivalent O(2)NaSrTbBi tetrahedra, corners with six equivalent O(1)Sr2TbBi trigonal pyramids, edges with two equivalent O(2)NaSrTbBi tetrahedra, and  an edgeedge with one O(1)Sr2TbBi trigonal pyramid. In the second O site, O(2) is bonded to one Na(1), one Sr(1), one Tb(1), and one Bi(1) atom to form distorted ONaSrTbBi tetrahedra that share corners with six equivalent O(2)NaSrTbBi tetrahedra, corners with four equivalent O(1)Sr2TbBi trigonal pyramids,  an edgeedge with one O(2)NaSrTbBi tetrahedra, and edges with two equivalent O(1)Sr2TbBi trigonal pyramids. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Na(2), one Sr(2), one Tb(1), and one Bi(1) atom.