Ni4Tl(PO4)3 crystallizes in the orthorhombic Cmc2_1 space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(3), one O(5), one O(8), and one O(9) atom to form NiO5 square pyramids that share  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra,  a cornercorner with one Ni(2)O5 trigonal bipyramid, and edges with two equivalent Ni(1)O5 square pyramids. In the second Ni site, Ni(2) is bonded to one O(1), one O(4), one O(8), and two equivalent O(6) atoms to form NiO5 trigonal bipyramids that share corners with two equivalent Ni(1)O5 square pyramids,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(2), and two equivalent O(7) atoms. Tl(1) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(7) atoms. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 square pyramids and corners with two equivalent Ni(2)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(3), one O(9), and two equivalent O(6) atoms to form PO4 tetrahedra that share corners with four equivalent Ni(1)O5 square pyramids and corners with two equivalent Ni(2)O5 trigonal bipyramids. In the third P site, P(3) is bonded to one O(5), one O(8), and two equivalent O(7) atoms to form PO4 tetrahedra that share corners with four equivalent Ni(1)O5 square pyramids and  a cornercorner with one Ni(2)O5 trigonal bipyramid. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ni(2) and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ni(1), one Ni(3), one Tl(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ni(3), two equivalent Ni(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Ni(2) and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ni(2) and one P(2) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Ni(3), one Tl(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a tetrahedral geometry to one Ni(2), two equivalent Ni(1), and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(2) atom.
Ni4Tl(PO4)3 crystallizes in the orthorhombic Cmc2_1 space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(3), one O(5), one O(8), and one O(9) atom to form NiO5 square pyramids that share  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra,  a cornercorner with one Ni(2)O5 trigonal bipyramid, and edges with two equivalent Ni(1)O5 square pyramids. The Ni(1)-O(2) bond length is 2.05 Å. The Ni(1)-O(3) bond length is 2.13 Å. The Ni(1)-O(5) bond length is 2.05 Å. The Ni(1)-O(8) bond length is 2.09 Å. The Ni(1)-O(9) bond length is 2.03 Å. In the second Ni site, Ni(2) is bonded to one O(1), one O(4), one O(8), and two equivalent O(6) atoms to form NiO5 trigonal bipyramids that share corners with two equivalent Ni(1)O5 square pyramids,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The Ni(2)-O(1) bond length is 1.99 Å. The Ni(2)-O(4) bond length is 1.95 Å. The Ni(2)-O(8) bond length is 2.15 Å. Both Ni(2)-O(6) bond lengths are 1.96 Å. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(2), and two equivalent O(7) atoms. The Ni(3)-O(3) bond length is 2.06 Å. Both Ni(3)-O(2) bond lengths are 2.22 Å. Both Ni(3)-O(7) bond lengths are 2.18 Å. Tl(1) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(7) atoms. Both Tl(1)-O(2) bond lengths are 2.79 Å. Both Tl(1)-O(7) bond lengths are 2.84 Å. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 square pyramids and corners with two equivalent Ni(2)O5 trigonal bipyramids. The P(1)-O(1) bond length is 1.54 Å. The P(1)-O(4) bond length is 1.51 Å. Both P(1)-O(2) bond lengths are 1.59 Å. In the second P site, P(2) is bonded to one O(3), one O(9), and two equivalent O(6) atoms to form PO4 tetrahedra that share corners with four equivalent Ni(1)O5 square pyramids and corners with two equivalent Ni(2)O5 trigonal bipyramids. The P(2)-O(3) bond length is 1.62 Å. The P(2)-O(9) bond length is 1.56 Å. Both P(2)-O(6) bond lengths are 1.51 Å. In the third P site, P(3) is bonded to one O(5), one O(8), and two equivalent O(7) atoms to form PO4 tetrahedra that share corners with four equivalent Ni(1)O5 square pyramids and  a cornercorner with one Ni(2)O5 trigonal bipyramid. The P(3)-O(5) bond length is 1.57 Å. The P(3)-O(8) bond length is 1.61 Å. Both P(3)-O(7) bond lengths are 1.54 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ni(2) and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ni(1), one Ni(3), one Tl(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ni(3), two equivalent Ni(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Ni(2) and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Ni(2) and one P(2) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Ni(3), one Tl(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a tetrahedral geometry to one Ni(2), two equivalent Ni(1), and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(2) atom.