Cu4O(PO4)2 crystallizes in the triclinic P-1 space group. There are four inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form distorted CuO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  a cornercorner with one Cu(2)O5 trigonal bipyramid, and  an edgeedge with one Cu(2)O5 trigonal bipyramid. In the second Cu site, Cu(2) is bonded to one O(2), one O(5), one O(7), one O(8), and one O(9) atom to form CuO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  a cornercorner with one Cu(1)O5 trigonal bipyramid, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. In the third Cu site, Cu(3) is bonded in a 6-coordinate geometry to one O(4), one O(5), one O(6), one O(7), and two equivalent O(1) atoms. In the fourth Cu site, Cu(4) is bonded in a rectangular see-saw-like geometry to one O(3), one O(5), one O(6), and one O(9) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Cu(1)O5 trigonal bipyramids and corners with two equivalent Cu(2)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(1), one O(2), one O(3), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Cu(1)O5 trigonal bipyramids and corners with two equivalent Cu(2)O5 trigonal bipyramids. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Cu(3) and one P(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(2), and one P(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(4), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(3), and one P(1) atom. In the fifth O site, O(5) is bonded in a tetrahedral geometry to one Cu(1), one Cu(2), one Cu(3), and one Cu(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Cu(3), one Cu(4), and one P(1) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Cu(2), one Cu(3), and one P(1) atom. In the eighth O site, O(8) is bonded in a trigonal non-coplanar geometry to one Cu(1), one Cu(2), and one P(1) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Cu(2), one Cu(4), and one P(2) atom.
Cu4O(PO4)2 crystallizes in the triclinic P-1 space group. There are four inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form distorted CuO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  a cornercorner with one Cu(2)O5 trigonal bipyramid, and  an edgeedge with one Cu(2)O5 trigonal bipyramid. The Cu(1)-O(2) bond length is 2.03 Å. The Cu(1)-O(3) bond length is 2.25 Å. The Cu(1)-O(4) bond length is 2.06 Å. The Cu(1)-O(5) bond length is 1.89 Å. The Cu(1)-O(8) bond length is 1.95 Å. In the second Cu site, Cu(2) is bonded to one O(2), one O(5), one O(7), one O(8), and one O(9) atom to form CuO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  a cornercorner with one Cu(1)O5 trigonal bipyramid, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. The Cu(2)-O(2) bond length is 2.26 Å. The Cu(2)-O(5) bond length is 1.90 Å. The Cu(2)-O(7) bond length is 1.95 Å. The Cu(2)-O(8) bond length is 1.96 Å. The Cu(2)-O(9) bond length is 2.10 Å. In the third Cu site, Cu(3) is bonded in a 6-coordinate geometry to one O(4), one O(5), one O(6), one O(7), and two equivalent O(1) atoms. The Cu(3)-O(4) bond length is 1.96 Å. The Cu(3)-O(5) bond length is 1.92 Å. The Cu(3)-O(6) bond length is 2.41 Å. The Cu(3)-O(7) bond length is 2.55 Å. There is one shorter (1.98 Å) and one longer (1.99 Å) Cu(3)-O(1) bond length. In the fourth Cu site, Cu(4) is bonded in a rectangular see-saw-like geometry to one O(3), one O(5), one O(6), and one O(9) atom. The Cu(4)-O(3) bond length is 1.95 Å. The Cu(4)-O(5) bond length is 1.93 Å. The Cu(4)-O(6) bond length is 1.92 Å. The Cu(4)-O(9) bond length is 1.94 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Cu(1)O5 trigonal bipyramids and corners with two equivalent Cu(2)O5 trigonal bipyramids. The P(1)-O(4) bond length is 1.54 Å. The P(1)-O(6) bond length is 1.53 Å. The P(1)-O(7) bond length is 1.51 Å. The P(1)-O(8) bond length is 1.58 Å. In the second P site, P(2) is bonded to one O(1), one O(2), one O(3), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Cu(1)O5 trigonal bipyramids and corners with two equivalent Cu(2)O5 trigonal bipyramids. The P(2)-O(1) bond length is 1.55 Å. The P(2)-O(2) bond length is 1.53 Å. The P(2)-O(3) bond length is 1.54 Å. The P(2)-O(9) bond length is 1.54 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Cu(3) and one P(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(2), and one P(2) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(4), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(3), and one P(1) atom. In the fifth O site, O(5) is bonded in a tetrahedral geometry to one Cu(1), one Cu(2), one Cu(3), and one Cu(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Cu(3), one Cu(4), and one P(1) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Cu(2), one Cu(3), and one P(1) atom. In the eighth O site, O(8) is bonded in a trigonal non-coplanar geometry to one Cu(1), one Cu(2), and one P(1) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Cu(2), one Cu(4), and one P(2) atom.