Ti11CuP8 crystallizes in the orthorhombic Pbam space group. There are six inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one P(2), two equivalent P(1), and two equivalent P(4) atoms to form distorted TiP5 trigonal bipyramids that share  a cornercorner with one Cu(1)Ti8P4 cuboctahedra, corners with two equivalent Ti(6)P6 octahedra, corners with four equivalent Ti(4)P5 square pyramids, edges with two equivalent Ti(4)P5 square pyramids, edges with two equivalent Ti(1)P5 trigonal bipyramids, and edges with four equivalent Ti(5)P5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 51°. In the second Ti site, Ti(2) is bonded in a 5-coordinate geometry to two equivalent Cu(1), one P(4), two equivalent P(2), and two equivalent P(3) atoms. In the third Ti site, Ti(3) is bonded in a 7-coordinate geometry to two equivalent Cu(1), one P(1), two equivalent P(2), and two equivalent P(3) atoms. In the fourth Ti site, Ti(4) is bonded to one P(3), two equivalent P(1), and two equivalent P(4) atoms to form distorted TiP5 square pyramids that share  a cornercorner with one Cu(1)Ti8P4 cuboctahedra, corners with two equivalent Ti(5)P5 trigonal bipyramids, corners with four equivalent Ti(1)P5 trigonal bipyramids, edges with two equivalent Ti(6)P6 octahedra, edges with two equivalent Ti(4)P5 square pyramids, edges with two equivalent Ti(1)P5 trigonal bipyramids, and edges with two equivalent Ti(5)P5 trigonal bipyramids. In the fifth Ti site, Ti(5) is bonded to one P(4), two equivalent P(1), and two equivalent P(2) atoms to form distorted TiP5 trigonal bipyramids that share corners with two equivalent Cu(1)Ti8P4 cuboctahedra,  a cornercorner with one Ti(6)P6 octahedra, corners with two equivalent Ti(4)P5 square pyramids, corners with four equivalent Ti(5)P5 trigonal bipyramids, edges with two equivalent Ti(4)P5 square pyramids, and edges with four equivalent Ti(1)P5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 37°. In the sixth Ti site, Ti(6) is bonded to two equivalent P(4) and four equivalent P(3) atoms to form TiP6 octahedra that share corners with four equivalent Cu(1)Ti8P4 cuboctahedra, corners with two equivalent Ti(5)P5 trigonal bipyramids, corners with four equivalent Ti(1)P5 trigonal bipyramids, edges with two equivalent Ti(6)P6 octahedra, and edges with four equivalent Ti(4)P5 square pyramids. Cu(1) is bonded to four equivalent Ti(2), four equivalent Ti(3), two equivalent P(2), and two equivalent P(3) atoms to form CuTi8P4 cuboctahedra that share corners with four equivalent Ti(6)P6 octahedra, corners with four equivalent P(1)Ti7 pentagonal bipyramids, corners with two equivalent Ti(4)P5 square pyramids, corners with two equivalent Ti(1)P5 trigonal bipyramids, corners with four equivalent Ti(5)P5 trigonal bipyramids, and faces with two equivalent Cu(1)Ti8P4 cuboctahedra. The corner-sharing octahedral tilt angles are 45°. There are four inequivalent P sites. In the first P site, P(3) is bonded in a 8-coordinate geometry to one Ti(4), two equivalent Ti(2), two equivalent Ti(3), two equivalent Ti(6), and one Cu(1) atom. In the second P site, P(4) is bonded in a 7-coordinate geometry to one Ti(2), one Ti(5), one Ti(6), two equivalent Ti(1), and two equivalent Ti(4) atoms. In the third P site, P(1) is bonded to one Ti(3), two equivalent Ti(1), two equivalent Ti(4), and two equivalent Ti(5) atoms to form distorted PTi7 pentagonal bipyramids that share corners with two equivalent Cu(1)Ti8P4 cuboctahedra, corners with two equivalent P(1)Ti7 pentagonal bipyramids, and edges with two equivalent P(1)Ti7 pentagonal bipyramids. In the fourth P site, P(2) is bonded in a 8-coordinate geometry to one Ti(1), two equivalent Ti(2), two equivalent Ti(3), two equivalent Ti(5), and one Cu(1) atom.
Ti11CuP8 crystallizes in the orthorhombic Pbam space group. There are six inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one P(2), two equivalent P(1), and two equivalent P(4) atoms to form distorted TiP5 trigonal bipyramids that share  a cornercorner with one Cu(1)Ti8P4 cuboctahedra, corners with two equivalent Ti(6)P6 octahedra, corners with four equivalent Ti(4)P5 square pyramids, edges with two equivalent Ti(4)P5 square pyramids, edges with two equivalent Ti(1)P5 trigonal bipyramids, and edges with four equivalent Ti(5)P5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 51°. The Ti(1)-P(2) bond length is 2.49 Å. Both Ti(1)-P(1) bond lengths are 2.47 Å. Both Ti(1)-P(4) bond lengths are 2.51 Å. In the second Ti site, Ti(2) is bonded in a 5-coordinate geometry to two equivalent Cu(1), one P(4), two equivalent P(2), and two equivalent P(3) atoms. Both Ti(2)-Cu(1) bond lengths are 2.76 Å. The Ti(2)-P(4) bond length is 2.44 Å. Both Ti(2)-P(2) bond lengths are 2.50 Å. Both Ti(2)-P(3) bond lengths are 2.57 Å. In the third Ti site, Ti(3) is bonded in a 7-coordinate geometry to two equivalent Cu(1), one P(1), two equivalent P(2), and two equivalent P(3) atoms. Both Ti(3)-Cu(1) bond lengths are 2.72 Å. The Ti(3)-P(1) bond length is 2.43 Å. Both Ti(3)-P(2) bond lengths are 2.56 Å. Both Ti(3)-P(3) bond lengths are 2.54 Å. In the fourth Ti site, Ti(4) is bonded to one P(3), two equivalent P(1), and two equivalent P(4) atoms to form distorted TiP5 square pyramids that share  a cornercorner with one Cu(1)Ti8P4 cuboctahedra, corners with two equivalent Ti(5)P5 trigonal bipyramids, corners with four equivalent Ti(1)P5 trigonal bipyramids, edges with two equivalent Ti(6)P6 octahedra, edges with two equivalent Ti(4)P5 square pyramids, edges with two equivalent Ti(1)P5 trigonal bipyramids, and edges with two equivalent Ti(5)P5 trigonal bipyramids. The Ti(4)-P(3) bond length is 2.50 Å. Both Ti(4)-P(1) bond lengths are 2.48 Å. Both Ti(4)-P(4) bond lengths are 2.46 Å. In the fifth Ti site, Ti(5) is bonded to one P(4), two equivalent P(1), and two equivalent P(2) atoms to form distorted TiP5 trigonal bipyramids that share corners with two equivalent Cu(1)Ti8P4 cuboctahedra,  a cornercorner with one Ti(6)P6 octahedra, corners with two equivalent Ti(4)P5 square pyramids, corners with four equivalent Ti(5)P5 trigonal bipyramids, edges with two equivalent Ti(4)P5 square pyramids, and edges with four equivalent Ti(1)P5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 37°. The Ti(5)-P(4) bond length is 2.71 Å. There is one shorter (2.49 Å) and one longer (2.54 Å) Ti(5)-P(1) bond length. Both Ti(5)-P(2) bond lengths are 2.51 Å. In the sixth Ti site, Ti(6) is bonded to two equivalent P(4) and four equivalent P(3) atoms to form TiP6 octahedra that share corners with four equivalent Cu(1)Ti8P4 cuboctahedra, corners with two equivalent Ti(5)P5 trigonal bipyramids, corners with four equivalent Ti(1)P5 trigonal bipyramids, edges with two equivalent Ti(6)P6 octahedra, and edges with four equivalent Ti(4)P5 square pyramids. Both Ti(6)-P(4) bond lengths are 2.56 Å. All Ti(6)-P(3) bond lengths are 2.62 Å. Cu(1) is bonded to four equivalent Ti(2), four equivalent Ti(3), two equivalent P(2), and two equivalent P(3) atoms to form CuTi8P4 cuboctahedra that share corners with four equivalent Ti(6)P6 octahedra, corners with four equivalent P(1)Ti7 pentagonal bipyramids, corners with two equivalent Ti(4)P5 square pyramids, corners with two equivalent Ti(1)P5 trigonal bipyramids, corners with four equivalent Ti(5)P5 trigonal bipyramids, and faces with two equivalent Cu(1)Ti8P4 cuboctahedra. The corner-sharing octahedral tilt angles are 45°. Both Cu(1)-P(2) bond lengths are 2.41 Å. Both Cu(1)-P(3) bond lengths are 2.79 Å. There are four inequivalent P sites. In the first P site, P(3) is bonded in a 8-coordinate geometry to one Ti(4), two equivalent Ti(2), two equivalent Ti(3), two equivalent Ti(6), and one Cu(1) atom. In the second P site, P(4) is bonded in a 7-coordinate geometry to one Ti(2), one Ti(5), one Ti(6), two equivalent Ti(1), and two equivalent Ti(4) atoms. In the third P site, P(1) is bonded to one Ti(3), two equivalent Ti(1), two equivalent Ti(4), and two equivalent Ti(5) atoms to form distorted PTi7 pentagonal bipyramids that share corners with two equivalent Cu(1)Ti8P4 cuboctahedra, corners with two equivalent P(1)Ti7 pentagonal bipyramids, and edges with two equivalent P(1)Ti7 pentagonal bipyramids. In the fourth P site, P(2) is bonded in a 8-coordinate geometry to one Ti(1), two equivalent Ti(2), two equivalent Ti(3), two equivalent Ti(5), and one Cu(1) atom.