Cr4Cu3(PO4)6 crystallizes in the triclinic P-1 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(11), one O(12), one O(2), one O(5), and two equivalent O(9) atoms to form CrO6 octahedra that share  a cornercorner with one Cu(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(3)O4 tetrahedra,  an edgeedge with one Cr(1)O6 octahedra, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 65°. In the second Cr site, Cr(2) is bonded to one O(1), one O(10), one O(3), one O(4), and two equivalent O(7) atoms to form CrO6 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,  an edgeedge with one Cr(2)O6 octahedra, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(12), one O(3), one O(4), one O(5), and one O(8) atom to form distorted CuO5 trigonal bipyramids that share  a cornercorner with one Cu(2)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Cr(1)O6 octahedra, and  an edgeedge with one Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles are 60°. In the second Cu site, Cu(2) is bonded to two equivalent O(2), two equivalent O(6), and two equivalent O(8) atoms to form CuO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra, 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 corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 65°. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(12), one O(2), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Cu(2)O6 octahedra, corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 34-61°. In the second P site, P(2) is bonded to one O(10), one O(11), one O(3), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cu(2)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-66°. In the third P site, P(3) is bonded to one O(5), one O(6), one O(7), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Cu(2)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, corners with three equivalent Cr(1)O6 octahedra, and  a cornercorner with one Cu(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 30-52°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cu(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Cr(2), one Cu(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Cr(2), one Cu(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cr(1), one Cu(1), and one P(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cu(2) and one P(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to two equivalent Cr(2) and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cu(2), and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to two equivalent Cr(1) and one P(3) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cu(1), and one P(1) atom.
Cr4Cu3(PO4)6 crystallizes in the triclinic P-1 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(11), one O(12), one O(2), one O(5), and two equivalent O(9) atoms to form CrO6 octahedra that share  a cornercorner with one Cu(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(3)O4 tetrahedra,  an edgeedge with one Cr(1)O6 octahedra, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 65°. The Cr(1)-O(11) bond length is 1.93 Å. The Cr(1)-O(12) bond length is 2.10 Å. The Cr(1)-O(2) bond length is 2.03 Å. The Cr(1)-O(5) bond length is 1.97 Å. There is one shorter (2.03 Å) and one longer (2.06 Å) Cr(1)-O(9) bond length. In the second Cr site, Cr(2) is bonded to one O(1), one O(10), one O(3), one O(4), and two equivalent O(7) atoms to form CrO6 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,  an edgeedge with one Cr(2)O6 octahedra, and  an edgeedge with one Cu(1)O5 trigonal bipyramid. The Cr(2)-O(1) bond length is 1.94 Å. The Cr(2)-O(10) bond length is 1.93 Å. The Cr(2)-O(3) bond length is 2.02 Å. The Cr(2)-O(4) bond length is 2.02 Å. There is one shorter (2.04 Å) and one longer (2.11 Å) Cr(2)-O(7) bond length. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(12), one O(3), one O(4), one O(5), and one O(8) atom to form distorted CuO5 trigonal bipyramids that share  a cornercorner with one Cu(2)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Cr(1)O6 octahedra, and  an edgeedge with one Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles are 60°. The Cu(1)-O(12) bond length is 2.04 Å. The Cu(1)-O(3) bond length is 2.07 Å. The Cu(1)-O(4) bond length is 2.03 Å. The Cu(1)-O(5) bond length is 2.28 Å. The Cu(1)-O(8) bond length is 1.93 Å. In the second Cu site, Cu(2) is bonded to two equivalent O(2), two equivalent O(6), and two equivalent O(8) atoms to form CuO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra, 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 corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 65°. Both Cu(2)-O(2) bond lengths are 2.30 Å. Both Cu(2)-O(6) bond lengths are 1.93 Å. Both Cu(2)-O(8) bond lengths are 2.39 Å. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(12), one O(2), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Cu(2)O6 octahedra, corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 34-61°. The P(1)-O(1) bond length is 1.51 Å. The P(1)-O(12) bond length is 1.58 Å. The P(1)-O(2) bond length is 1.56 Å. The P(1)-O(4) bond length is 1.58 Å. In the second P site, P(2) is bonded to one O(10), one O(11), one O(3), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cu(2)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-66°. The P(2)-O(10) bond length is 1.52 Å. The P(2)-O(11) bond length is 1.52 Å. The P(2)-O(3) bond length is 1.58 Å. The P(2)-O(8) bond length is 1.57 Å. In the third P site, P(3) is bonded to one O(5), one O(6), one O(7), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Cu(2)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, corners with three equivalent Cr(1)O6 octahedra, and  a cornercorner with one Cu(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 30-52°. The P(3)-O(5) bond length is 1.55 Å. The P(3)-O(6) bond length is 1.51 Å. The P(3)-O(7) bond length is 1.58 Å. The P(3)-O(9) bond length is 1.59 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cu(2), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Cr(2), one Cu(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Cr(2), one Cu(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cr(1), one Cu(1), and one P(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cu(2) and one P(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to two equivalent Cr(2) and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cu(2), and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to two equivalent Cr(1) and one P(3) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cu(1), and one P(1) atom.