Ni5(PO4)4 crystallizes in the triclinic P-1 space group. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(13), one O(3), one O(5), one O(7), and one O(9) atom to form NiO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra,  an edgeedge with one Ni(3)O6 octahedra, and  an edgeedge with one Ni(4)O6 octahedra. In the second Ni site, Ni(2) is bonded to one O(10), one O(14), one O(4), one O(6), and one O(8) atom to form NiO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra,  an edgeedge with one Ni(3)O6 octahedra, and  an edgeedge with one Ni(4)O6 octahedra. In the third Ni site, Ni(3) is bonded to one O(11), one O(13), one O(2), one O(4), one O(6), and one O(7) atom to form NiO6 octahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one Ni(5)O6 octahedra,  an edgeedge with one P(3)O4 tetrahedra,  an edgeedge with one Ni(1)O5 trigonal bipyramid, and  an edgeedge with one Ni(2)O5 trigonal bipyramid. In the fourth Ni site, Ni(4) is bonded to one O(1), one O(12), one O(14), one O(3), one O(5), and one O(8) atom to form NiO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Ni(6)O6 octahedra,  an edgeedge with one P(4)O4 tetrahedra,  an edgeedge with one Ni(1)O5 trigonal bipyramid, and  an edgeedge with one Ni(2)O5 trigonal bipyramid. In the fifth Ni site, Ni(5) is bonded to two equivalent O(11), two equivalent O(15), and two equivalent O(2) atoms to form NiO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and edges with two equivalent Ni(3)O6 octahedra. In the sixth Ni site, Ni(6) is bonded to two equivalent O(1), two equivalent O(12), and two equivalent O(16) atoms to form NiO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and edges with two equivalent Ni(4)O6 octahedra. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(12), one O(13), one O(15), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one Ni(5)O6 octahedra,  a cornercorner with one Ni(6)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra,  a cornercorner with one Ni(1)O5 trigonal bipyramid, and  a cornercorner with one Ni(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-53°. In the second P site, P(2) is bonded to one O(11), one O(14), one O(16), and one O(3) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(5)O6 octahedra,  a cornercorner with one Ni(6)O6 octahedra, corners with two equivalent Ni(4)O6 octahedra,  a cornercorner with one Ni(1)O5 trigonal bipyramid, and  a cornercorner with one Ni(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-53°. In the third P site, P(3) is bonded to one O(1), one O(6), one O(7), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one Ni(6)O6 octahedra,  a cornercorner with one Ni(2)O5 trigonal bipyramid, corners with two equivalent Ni(1)O5 trigonal bipyramids, and  an edgeedge with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-52°. In the fourth P site, P(4) is bonded to one O(10), one O(2), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(5)O6 octahedra,  a cornercorner with one Ni(1)O5 trigonal bipyramid, corners with two equivalent Ni(2)O5 trigonal bipyramids, and  an edgeedge with one Ni(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-52°. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ni(4), one Ni(6), and one P(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ni(3), one Ni(5), and one P(4) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(4), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(3), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Ni(1), one Ni(4), and one P(4) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Ni(2), one Ni(3), and one P(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Ni(1), one Ni(3), and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Ni(2), one Ni(4), and one P(4) atom. In the ninth O site, O(9) is bonded in a linear geometry to one Ni(1) and one P(3) atom. In the tenth O site, O(10) is bonded in a linear geometry to one Ni(2) and one P(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Ni(3), one Ni(5), and one P(2) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Ni(4), one Ni(6), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Ni(1), one Ni(3), and one P(1) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Ni(2), one Ni(4), and one P(2) atom. In the fifteenth O site, O(15) is bonded in a distorted bent 150 degrees geometry to one Ni(5) and one P(1) atom. In the sixteenth O site, O(16) is bonded in a distorted bent 150 degrees geometry to one Ni(6) and one P(2) atom.
Ni5(PO4)4 crystallizes in the triclinic P-1 space group. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(13), one O(3), one O(5), one O(7), and one O(9) atom to form NiO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra,  an edgeedge with one Ni(3)O6 octahedra, and  an edgeedge with one Ni(4)O6 octahedra. The Ni(1)-O(13) bond length is 2.03 Å. The Ni(1)-O(3) bond length is 2.03 Å. The Ni(1)-O(5) bond length is 2.03 Å. The Ni(1)-O(7) bond length is 2.02 Å. The Ni(1)-O(9) bond length is 1.93 Å. In the second Ni site, Ni(2) is bonded to one O(10), one O(14), one O(4), one O(6), and one O(8) atom to form NiO5 trigonal bipyramids that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra,  an edgeedge with one Ni(3)O6 octahedra, and  an edgeedge with one Ni(4)O6 octahedra. The Ni(2)-O(10) bond length is 1.94 Å. The Ni(2)-O(14) bond length is 2.03 Å. The Ni(2)-O(4) bond length is 2.03 Å. The Ni(2)-O(6) bond length is 2.03 Å. The Ni(2)-O(8) bond length is 2.01 Å. In the third Ni site, Ni(3) is bonded to one O(11), one O(13), one O(2), one O(4), one O(6), and one O(7) atom to form NiO6 octahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one Ni(5)O6 octahedra,  an edgeedge with one P(3)O4 tetrahedra,  an edgeedge with one Ni(1)O5 trigonal bipyramid, and  an edgeedge with one Ni(2)O5 trigonal bipyramid. The Ni(3)-O(11) bond length is 2.03 Å. The Ni(3)-O(13) bond length is 2.13 Å. The Ni(3)-O(2) bond length is 2.06 Å. The Ni(3)-O(4) bond length is 2.02 Å. The Ni(3)-O(6) bond length is 2.04 Å. The Ni(3)-O(7) bond length is 2.10 Å. In the fourth Ni site, Ni(4) is bonded to one O(1), one O(12), one O(14), one O(3), one O(5), and one O(8) atom to form NiO6 octahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Ni(6)O6 octahedra,  an edgeedge with one P(4)O4 tetrahedra,  an edgeedge with one Ni(1)O5 trigonal bipyramid, and  an edgeedge with one Ni(2)O5 trigonal bipyramid. The Ni(4)-O(1) bond length is 2.06 Å. The Ni(4)-O(12) bond length is 2.03 Å. The Ni(4)-O(14) bond length is 2.13 Å. The Ni(4)-O(3) bond length is 2.01 Å. The Ni(4)-O(5) bond length is 2.04 Å. The Ni(4)-O(8) bond length is 2.09 Å. In the fifth Ni site, Ni(5) is bonded to two equivalent O(11), two equivalent O(15), and two equivalent O(2) atoms to form NiO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and edges with two equivalent Ni(3)O6 octahedra. Both Ni(5)-O(11) bond lengths are 2.22 Å. Both Ni(5)-O(15) bond lengths are 2.00 Å. Both Ni(5)-O(2) bond lengths are 2.11 Å. In the sixth Ni site, Ni(6) is bonded to two equivalent O(1), two equivalent O(12), and two equivalent O(16) atoms to form NiO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and edges with two equivalent Ni(4)O6 octahedra. Both Ni(6)-O(1) bond lengths are 2.11 Å. Both Ni(6)-O(12) bond lengths are 2.22 Å. Both Ni(6)-O(16) bond lengths are 2.00 Å. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(12), one O(13), one O(15), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one Ni(5)O6 octahedra,  a cornercorner with one Ni(6)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra,  a cornercorner with one Ni(1)O5 trigonal bipyramid, and  a cornercorner with one Ni(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-53°. The P(1)-O(12) bond length is 1.56 Å. The P(1)-O(13) bond length is 1.56 Å. The P(1)-O(15) bond length is 1.52 Å. The P(1)-O(4) bond length is 1.57 Å. In the second P site, P(2) is bonded to one O(11), one O(14), one O(16), and one O(3) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(5)O6 octahedra,  a cornercorner with one Ni(6)O6 octahedra, corners with two equivalent Ni(4)O6 octahedra,  a cornercorner with one Ni(1)O5 trigonal bipyramid, and  a cornercorner with one Ni(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-53°. The P(2)-O(11) bond length is 1.56 Å. The P(2)-O(14) bond length is 1.56 Å. The P(2)-O(16) bond length is 1.52 Å. The P(2)-O(3) bond length is 1.57 Å. In the third P site, P(3) is bonded to one O(1), one O(6), one O(7), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one Ni(6)O6 octahedra,  a cornercorner with one Ni(2)O5 trigonal bipyramid, corners with two equivalent Ni(1)O5 trigonal bipyramids, and  an edgeedge with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-52°. The P(3)-O(1) bond length is 1.54 Å. The P(3)-O(6) bond length is 1.57 Å. The P(3)-O(7) bond length is 1.59 Å. The P(3)-O(9) bond length is 1.50 Å. In the fourth P site, P(4) is bonded to one O(10), one O(2), one O(5), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(5)O6 octahedra,  a cornercorner with one Ni(1)O5 trigonal bipyramid, corners with two equivalent Ni(2)O5 trigonal bipyramids, and  an edgeedge with one Ni(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-52°. The P(4)-O(10) bond length is 1.50 Å. The P(4)-O(2) bond length is 1.54 Å. The P(4)-O(5) bond length is 1.57 Å. The P(4)-O(8) bond length is 1.59 Å. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ni(4), one Ni(6), and one P(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ni(3), one Ni(5), and one P(4) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(4), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(3), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Ni(1), one Ni(4), and one P(4) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Ni(2), one Ni(3), and one P(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Ni(1), one Ni(3), and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Ni(2), one Ni(4), and one P(4) atom. In the ninth O site, O(9) is bonded in a linear geometry to one Ni(1) and one P(3) atom. In the tenth O site, O(10) is bonded in a linear geometry to one Ni(2) and one P(4) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Ni(3), one Ni(5), and one P(2) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Ni(4), one Ni(6), and one P(1) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to one Ni(1), one Ni(3), and one P(1) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Ni(2), one Ni(4), and one P(2) atom. In the fifteenth O site, O(15) is bonded in a distorted bent 150 degrees geometry to one Ni(5) and one P(1) atom. In the sixteenth O site, O(16) is bonded in a distorted bent 150 degrees geometry to one Ni(6) and one P(2) atom.