Cu2(OH)PO4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form distorted CuO6 octahedra that share corners with four equivalent P(1)O4 tetrahedra, corners with four equivalent Cu(2)O5 trigonal bipyramids, and edges with two equivalent Cu(1)O6 octahedra. In the second Cu site, Cu(2) is bonded to one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form CuO5 trigonal bipyramids that share corners with four equivalent Cu(1)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, and  an edgeedge with one Cu(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 54-71°. P(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form PO4 tetrahedra that share corners with four equivalent Cu(1)O6 octahedra and corners with four equivalent Cu(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 52-65°. H(1) is bonded in a single-bond geometry to one O(4) atom. There are five inequivalent O sites. In the first O site, O(5) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(2), and one P(1) atom. In the second O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Cu(1) and one P(1) atom. In the third O site, O(2) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(2), and one P(1) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cu(2) and one P(1) atom. In the fifth O site, O(4) is bonded in a distorted single-bond geometry to one Cu(2), two equivalent Cu(1), and one H(1) atom.
Cu2(OH)PO4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form distorted CuO6 octahedra that share corners with four equivalent P(1)O4 tetrahedra, corners with four equivalent Cu(2)O5 trigonal bipyramids, and edges with two equivalent Cu(1)O6 octahedra. The Cu(1)-O(2) bond length is 2.43 Å. The Cu(1)-O(5) bond length is 2.44 Å. There is one shorter (1.98 Å) and one longer (1.99 Å) Cu(1)-O(1) bond length. There is one shorter (1.99 Å) and one longer (2.00 Å) Cu(1)-O(4) bond length. In the second Cu site, Cu(2) is bonded to one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form CuO5 trigonal bipyramids that share corners with four equivalent Cu(1)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, and  an edgeedge with one Cu(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 54-71°. The Cu(2)-O(2) bond length is 2.11 Å. The Cu(2)-O(4) bond length is 1.93 Å. The Cu(2)-O(5) bond length is 2.04 Å. There is one shorter (1.96 Å) and one longer (2.10 Å) Cu(2)-O(3) bond length. P(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form PO4 tetrahedra that share corners with four equivalent Cu(1)O6 octahedra and corners with four equivalent Cu(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 52-65°. The P(1)-O(1) bond length is 1.58 Å. The P(1)-O(2) bond length is 1.54 Å. The P(1)-O(3) bond length is 1.57 Å. The P(1)-O(5) bond length is 1.55 Å. H(1) is bonded in a single-bond geometry to one O(4) atom. The H(1)-O(4) bond length is 0.99 Å. There are five inequivalent O sites. In the first O site, O(5) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(2), and one P(1) atom. In the second O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Cu(1) and one P(1) atom. In the third O site, O(2) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(2), and one P(1) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Cu(2) and one P(1) atom. In the fifth O site, O(4) is bonded in a distorted single-bond geometry to one Cu(2), two equivalent Cu(1), and one H(1) atom.