CaCr3P3O13 crystallizes in the monoclinic P2_1/m space group. Ca(1) is bonded to one O(9), two equivalent O(2), two equivalent O(4), and two equivalent O(8) atoms to form distorted CaO7 pentagonal bipyramids that share corners with two equivalent Cr(3)O6 octahedra, corners with three equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(2)O5 square pyramids, corners with three equivalent P(3)O4 tetrahedra,  an edgeedge with one P(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-60°. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(5), one O(6), one O(9), and two equivalent O(8) atoms to form CrO6 octahedra that share corners with two equivalent Cr(3)O6 octahedra, corners with three equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one Cr(2)O5 square pyramid,  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. In the second Cr site, Cr(2) is bonded to one O(1), one O(3), one O(7), and two equivalent O(2) atoms to form CrO5 square pyramids that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and corners with three equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. In the third Cr site, Cr(3) is bonded to two equivalent O(10), two equivalent O(4), and two equivalent O(6) atoms to form CrO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and edges with two equivalent Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(5), one O(7), and two equivalent O(2) atoms to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with three equivalent Cr(2)O5 square pyramids, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 35°. In the second P site, P(2) is bonded to one O(10), one O(3), and two equivalent O(8) atoms to form PO4 tetrahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(3)O6 octahedra,  a cornercorner with one Cr(2)O5 square pyramid, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 42-55°. In the third P site, P(3) is bonded to one O(1), one O(9), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with two equivalent Cr(3)O6 octahedra, corners with three equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one Cr(2)O5 square pyramid, and  an edgeedge with one Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are ten inequivalent O sites. In the first O site, O(10) is bonded in a distorted trigonal planar geometry to two equivalent Cr(3) and one P(2) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Cr(1), one Cr(2), and one P(3) atom. In the third O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Cr(2), and one P(1) atom. In the fourth O site, O(3) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(2) atom. In the fifth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ca(1), one Cr(3), and one P(3) atom. In the sixth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(1) atom. In the seventh O site, O(6) is bonded in a trigonal planar geometry to one Cr(1) and two equivalent Cr(3) atoms. In the eighth O site, O(7) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(1) atom. In the ninth O site, O(8) is bonded in a 3-coordinate geometry to one Ca(1), one Cr(1), and one P(2) atom. In the tenth O site, O(9) is bonded in a 3-coordinate geometry to one Ca(1), one Cr(1), and one P(3) atom.
CaCr3P3O13 crystallizes in the monoclinic P2_1/m space group. Ca(1) is bonded to one O(9), two equivalent O(2), two equivalent O(4), and two equivalent O(8) atoms to form distorted CaO7 pentagonal bipyramids that share corners with two equivalent Cr(3)O6 octahedra, corners with three equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(2)O5 square pyramids, corners with three equivalent P(3)O4 tetrahedra,  an edgeedge with one P(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-60°. The Ca(1)-O(9) bond length is 2.45 Å. Both Ca(1)-O(2) bond lengths are 2.57 Å. Both Ca(1)-O(4) bond lengths are 2.46 Å. Both Ca(1)-O(8) bond lengths are 2.46 Å. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(5), one O(6), one O(9), and two equivalent O(8) atoms to form CrO6 octahedra that share corners with two equivalent Cr(3)O6 octahedra, corners with three equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one Cr(2)O5 square pyramid,  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. The Cr(1)-O(1) bond length is 2.14 Å. The Cr(1)-O(5) bond length is 1.97 Å. The Cr(1)-O(6) bond length is 1.92 Å. The Cr(1)-O(9) bond length is 2.14 Å. Both Cr(1)-O(8) bond lengths are 2.00 Å. In the second Cr site, Cr(2) is bonded to one O(1), one O(3), one O(7), and two equivalent O(2) atoms to form CrO5 square pyramids that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and corners with three equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. The Cr(2)-O(1) bond length is 1.98 Å. The Cr(2)-O(3) bond length is 1.95 Å. The Cr(2)-O(7) bond length is 1.92 Å. Both Cr(2)-O(2) bond lengths are 2.00 Å. In the third Cr site, Cr(3) is bonded to two equivalent O(10), two equivalent O(4), and two equivalent O(6) atoms to form CrO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and edges with two equivalent Cr(3)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. Both Cr(3)-O(10) bond lengths are 2.09 Å. Both Cr(3)-O(4) bond lengths are 2.03 Å. Both Cr(3)-O(6) bond lengths are 2.01 Å. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(5), one O(7), and two equivalent O(2) atoms to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with three equivalent Cr(2)O5 square pyramids, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 35°. The P(1)-O(5) bond length is 1.53 Å. The P(1)-O(7) bond length is 1.54 Å. Both P(1)-O(2) bond lengths are 1.56 Å. In the second P site, P(2) is bonded to one O(10), one O(3), and two equivalent O(8) atoms to form PO4 tetrahedra that share corners with two equivalent Cr(1)O6 octahedra, corners with two equivalent Cr(3)O6 octahedra,  a cornercorner with one Cr(2)O5 square pyramid, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 42-55°. The P(2)-O(10) bond length is 1.59 Å. The P(2)-O(3) bond length is 1.52 Å. Both P(2)-O(8) bond lengths are 1.55 Å. In the third P site, P(3) is bonded to one O(1), one O(9), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with two equivalent Cr(3)O6 octahedra, corners with three equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one Cr(2)O5 square pyramid, and  an edgeedge with one Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles are 50°. The P(3)-O(1) bond length is 1.57 Å. The P(3)-O(9) bond length is 1.55 Å. Both P(3)-O(4) bond lengths are 1.54 Å. There are ten inequivalent O sites. In the first O site, O(10) is bonded in a distorted trigonal planar geometry to two equivalent Cr(3) and one P(2) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Cr(1), one Cr(2), and one P(3) atom. In the third O site, O(2) is bonded in a 3-coordinate geometry to one Ca(1), one Cr(2), and one P(1) atom. In the fourth O site, O(3) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(2) atom. In the fifth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ca(1), one Cr(3), and one P(3) atom. In the sixth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(1) atom. In the seventh O site, O(6) is bonded in a trigonal planar geometry to one Cr(1) and two equivalent Cr(3) atoms. In the eighth O site, O(7) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(1) atom. In the ninth O site, O(8) is bonded in a 3-coordinate geometry to one Ca(1), one Cr(1), and one P(2) atom. In the tenth O site, O(9) is bonded in a 3-coordinate geometry to one Ca(1), one Cr(1), and one P(3) atom.