The structure described by Ti20Se19 crystallizes in the triclinic P1 space group. There are twenty inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one Se(1), one Se(12), one Se(17), one Se(2), one Se(3), and one Se(5) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra, corners with two equivalent Ti(19)Se6 octahedra, corners with two equivalent Ti(5)Se6 octahedra, corners with two equivalent Ti(9)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(20)Se5 square pyramid,  an edgeedge with one Ti(15)Se5 trigonal bipyramid,  a faceface with one Ti(2)Se6 octahedra, and  a faceface with one Ti(4)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the second Ti site, Ti(2) is bonded to one Se(1), one Se(16), one Se(17), one Se(2), one Se(3), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra, corners with two equivalent Ti(10)Se6 octahedra, corners with two equivalent Ti(6)Se6 octahedra,  a cornercorner with one Ti(18)Se5 square pyramid, corners with two equivalent Ti(20)Se5 square pyramids,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(16)Se5 square pyramid,  an edgeedge with one Ti(17)Se5 square pyramid,  a faceface with one Ti(1)Se6 octahedra, and  a faceface with one Ti(15)Se5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 39-54°. In the third Ti site, Ti(3) is bonded to one Se(10), one Se(15), one Se(2), one Se(4), one Se(5), and one Se(6) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra, corners with two equivalent Ti(5)Se6 octahedra, corners with two equivalent Ti(9)Se6 octahedra,  a cornercorner with one Ti(17)Se5 square pyramid, corners with two equivalent Ti(13)Se5 square pyramids,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid,  a faceface with one Ti(4)Se6 octahedra, and  a faceface with one Ti(8)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the fourth Ti site, Ti(4) is bonded to one Se(12), one Se(2), one Se(3), one Se(4), one Se(5), and one Se(6) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(10)Se6 octahedra, corners with two equivalent Ti(14)Se6 octahedra, corners with two equivalent Ti(6)Se6 octahedra,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid,  a faceface with one Ti(1)Se6 octahedra, and  a faceface with one Ti(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 41-55°. In the fifth Ti site, Ti(5) is bonded to one Se(1), one Se(19), one Se(4), one Se(5), one Se(7), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(1)Se6 octahedra, corners with two equivalent Ti(3)Se6 octahedra,  a cornercorner with one Ti(20)Se5 square pyramid, corners with two equivalent Ti(15)Se5 trigonal bipyramids,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(16)Se5 square pyramid,  a faceface with one Ti(10)Se6 octahedra, and  a faceface with one Ti(6)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the sixth Ti site, Ti(6) is bonded to one Se(14), one Se(17), one Se(19), one Se(4), one Se(5), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(2)Se6 octahedra, corners with two equivalent Ti(4)Se6 octahedra,  a cornercorner with one Ti(17)Se5 square pyramid, corners with two equivalent Ti(16)Se5 square pyramids,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(20)Se5 square pyramid,  an edgeedge with one Ti(15)Se5 trigonal bipyramid,  a faceface with one Ti(19)Se6 octahedra, and  a faceface with one Ti(5)Se6 octahedra. The corner-sharing octahedral tilt angles range from 41-54°. In the seventh Ti site, Ti(7) is bonded to one Se(10), one Se(13), one Se(18), one Se(6), one Se(7), and one Se(9) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra, corners with two equivalent Ti(9)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid, corners with two equivalent Ti(13)Se5 square pyramids, corners with two equivalent Ti(17)Se5 square pyramids,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid,  an edgeedge with one Ti(20)Se5 square pyramid,  a faceface with one Ti(12)Se6 octahedra, and  a faceface with one Ti(8)Se6 octahedra. The corner-sharing octahedral tilt angles range from 41-54°. In the eighth Ti site, Ti(8) is bonded to one Se(10), one Se(15), one Se(5), one Se(6), one Se(7), and one Se(9) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(10)Se6 octahedra, corners with two equivalent Ti(14)Se6 octahedra,  a cornercorner with one Ti(20)Se5 square pyramid, corners with two equivalent Ti(18)Se5 square pyramids,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid,  an edgeedge with one Ti(17)Se5 square pyramid,  a faceface with one Ti(3)Se6 octahedra, and  a faceface with one Ti(7)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-54°. In the ninth Ti site, Ti(9) is bonded to one Se(10), one Se(11), one Se(12), one Se(2), one Se(7), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra, corners with two equivalent Ti(1)Se6 octahedra, corners with two equivalent Ti(3)Se6 octahedra, corners with two equivalent Ti(7)Se6 octahedra,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid,  a faceface with one Ti(10)Se6 octahedra, and  a faceface with one Ti(14)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-56°. In the tenth Ti site, Ti(10) is bonded to one Se(1), one Se(10), one Se(12), one Se(4), one Se(7), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(2)Se6 octahedra, corners with two equivalent Ti(4)Se6 octahedra, corners with two equivalent Ti(8)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(15)Se5 trigonal bipyramid,  a faceface with one Ti(5)Se6 octahedra, and  a faceface with one Ti(9)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the eleventh Ti site, Ti(11) is bonded to one Se(11), one Se(13), one Se(14), one Se(16), one Se(19), and one Se(9) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(19)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid, corners with two equivalent Ti(13)Se5 square pyramids, corners with two equivalent Ti(17)Se5 square pyramids,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid,  an edgeedge with one Ti(20)Se5 square pyramid,  an edgeedge with one Ti(15)Se5 trigonal bipyramid,  a faceface with one Ti(12)Se6 octahedra, and  a faceface with one Ti(16)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 40-57°. In the twelfth Ti site, Ti(12) is bonded to one Se(10), one Se(11), one Se(13), one Se(14), one Se(18), and one Se(9) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(14)Se6 octahedra, corners with two equivalent Ti(18)Se5 square pyramids, corners with two equivalent Ti(20)Se5 square pyramids,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid,  an edgeedge with one Ti(16)Se5 square pyramid,  an edgeedge with one Ti(17)Se5 square pyramid,  a faceface with one Ti(11)Se6 octahedra, and  a faceface with one Ti(7)Se6 octahedra. The corner-sharing octahedral tilt angles range from 42-54°. In the thirteenth Ti site, Ti(13) is bonded to one Se(11), one Se(12), one Se(13), one Se(15), and one Se(6) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra, corners with two equivalent Ti(11)Se6 octahedra, corners with two equivalent Ti(3)Se6 octahedra, corners with two equivalent Ti(7)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  a cornercorner with one Ti(18)Se5 square pyramid,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid, and  a faceface with one Ti(14)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-54°. In the fourteenth Ti site, Ti(14) is bonded to one Se(11), one Se(12), one Se(13), one Se(15), one Se(2), and one Se(7) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(12)Se6 octahedra, corners with two equivalent Ti(4)Se6 octahedra, corners with two equivalent Ti(8)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid,  a faceface with one Ti(9)Se6 octahedra, and  a faceface with one Ti(13)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 39-54°. In the fifteenth Ti site, Ti(15) is bonded to one Se(1), one Se(14), one Se(16), one Se(3), and one Se(8) atom to form distorted TiSe5 trigonal bipyramids that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(19)Se6 octahedra, corners with two equivalent Ti(5)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(16)Se5 square pyramid, and  a faceface with one Ti(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-54°. In the sixteenth Ti site, Ti(16) is bonded to one Se(1), one Se(13), one Se(14), one Se(16), and one Se(19) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(6)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(15)Se5 trigonal bipyramid, and  a faceface with one Ti(11)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-55°. In the seventeenth Ti site, Ti(17) is bonded to one Se(15), one Se(16), one Se(17), one Se(18), and one Se(9) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra, corners with two equivalent Ti(11)Se6 octahedra, corners with two equivalent Ti(7)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(20)Se5 square pyramid, and  a faceface with one Ti(18)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 40-54°. In the eighteenth Ti site, Ti(18) is bonded to one Se(11), one Se(15), one Se(16), one Se(18), and one Se(6) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(12)Se6 octahedra, corners with two equivalent Ti(8)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid, and  a faceface with one Ti(17)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 38-54°. In the nineteenth Ti site, Ti(19) is bonded to one Se(14), one Se(17), one Se(18), one Se(19), one Se(3), and one Se(4) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(1)Se6 octahedra, corners with two equivalent Ti(11)Se6 octahedra,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid, corners with two equivalent Ti(15)Se5 trigonal bipyramids,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(16)Se5 square pyramid,  an edgeedge with one Ti(17)Se5 square pyramid,  a faceface with one Ti(6)Se6 octahedra, and  a faceface with one Ti(20)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 40-57°. In the twentieth Ti site, Ti(20) is bonded to one Se(17), one Se(18), one Se(19), one Se(3), and one Se(9) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra, corners with two equivalent Ti(12)Se6 octahedra, corners with two equivalent Ti(2)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(17)Se5 square pyramid, and  a faceface with one Ti(19)Se6 octahedra. The corner-sharing octahedral tilt angles range from 38-55°. There are nineteen inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(10), one Ti(15), one Ti(16), one Ti(2), and one Ti(5) atom. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(14), one Ti(2), one Ti(3), one Ti(4), and one Ti(9) atom. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(15), one Ti(19), one Ti(2), one Ti(20), and one Ti(4) atom. In the fourth Se site, Se(4) is bonded in a 6-coordinate geometry to one Ti(10), one Ti(19), one Ti(3), one Ti(4), one Ti(5), and one Ti(6) atom. In the fifth Se site, Se(5) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(3), one Ti(4), one Ti(5), one Ti(6), and one Ti(8) atom. In the sixth Se site, Se(6) is bonded in a 6-coordinate geometry to one Ti(13), one Ti(18), one Ti(3), one Ti(4), one Ti(7), and one Ti(8) atom. In the seventh Se site, Se(7) is bonded in a 6-coordinate geometry to one Ti(10), one Ti(14), one Ti(5), one Ti(7), one Ti(8), and one Ti(9) atom. In the eighth Se site, Se(8) is bonded in a 6-coordinate geometry to one Ti(10), one Ti(15), one Ti(2), one Ti(5), one Ti(6), and one Ti(9) atom. In the ninth Se site, Se(9) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(12), one Ti(17), one Ti(20), one Ti(7), and one Ti(8) atom. In the tenth Se site, Se(10) is bonded in a 6-coordinate geometry to one Ti(10), one Ti(12), one Ti(3), one Ti(7), one Ti(8), and one Ti(9) atom. In the eleventh Se site, Se(11) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(12), one Ti(13), one Ti(14), one Ti(18), and one Ti(9) atom. In the twelfth Se site, Se(12) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(10), one Ti(13), one Ti(14), one Ti(4), and one Ti(9) atom. In the thirteenth Se site, Se(13) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(12), one Ti(13), one Ti(14), one Ti(16), and one Ti(7) atom. In the fourteenth Se site, Se(14) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(12), one Ti(15), one Ti(16), one Ti(19), and one Ti(6) atom. In the fifteenth Se site, Se(15) is bonded in a 6-coordinate geometry to one Ti(13), one Ti(14), one Ti(17), one Ti(18), one Ti(3), and one Ti(8) atom. In the sixteenth Se site, Se(16) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(15), one Ti(16), one Ti(17), one Ti(18), and one Ti(2) atom. In the seventeenth Se site, Se(17) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(17), one Ti(19), one Ti(2), one Ti(20), and one Ti(6) atom. In the eighteenth Se site, Se(18) is bonded in a 6-coordinate geometry to one Ti(12), one Ti(17), one Ti(18), one Ti(19), one Ti(20), and one Ti(7) atom. In the nineteenth Se site, Se(19) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(16), one Ti(19), one Ti(20), one Ti(5), and one Ti(6) atom. is represented by the CIF card [CIF]
data_Ti20Se19
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   17.156
_cell_length_b   9.273
_cell_length_c   7.349
_cell_angle_alpha   69.766
_cell_angle_beta   62.185
_cell_angle_gamma   42.236
_symmetry_Int_Tables_number   1
_cell_volume   695.048
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ti  Ti0  1  0.172  0.193  0.005  1.0
  Ti  Ti1  1  0.025  0.307  0.508  1.0
  Ti  Ti2  1  0.372  0.192  0.007  1.0
  Ti  Ti3  1  0.226  0.305  0.507  1.0
  Ti  Ti4  1  0.172  0.696  0.494  1.0
  Ti  Ti5  1  0.028  0.806  0.994  1.0
  Ti  Ti6  1  0.573  0.190  0.006  1.0
  Ti  Ti7  1  0.428  0.305  0.507  1.0
  Ti  Ti8  1  0.375  0.693  0.493  1.0
  Ti  Ti9  1  0.229  0.807  0.994  1.0
  Ti  Ti10  1  0.771  0.192  0.006  1.0
  Ti  Ti11  1  0.627  0.303  0.507  1.0
  Ti  Ti12  1  0.575  0.693  0.495  1.0
  Ti  Ti13  1  0.431  0.804  0.993  1.0
  Ti  Ti14  1  0.970  0.200  0.001  1.0
  Ti  Ti15  1  0.826  0.311  0.505  1.0
  Ti  Ti16  1  0.772  0.693  0.494  1.0
  Ti  Ti17  1  0.630  0.803  0.990  1.0
  Ti  Ti18  1  0.972  0.695  0.492  1.0
  Ti  Ti19  1  0.831  0.803  0.990  1.0
  Se  Se20  1  0.059  0.085  0.281  1.0
  Se  Se21  1  0.262  0.077  0.285  1.0
  Se  Se22  1  0.020  0.426  0.789  1.0
  Se  Se23  1  0.175  0.579  0.215  1.0
  Se  Se24  1  0.224  0.422  0.784  1.0
  Se  Se25  1  0.464  0.074  0.284  1.0
  Se  Se26  1  0.376  0.577  0.216  1.0
  Se  Se27  1  0.137  0.923  0.717  1.0
  Se  Se28  1  0.664  0.073  0.283  1.0
  Se  Se29  1  0.424  0.421  0.786  1.0
  Se  Se30  1  0.579  0.577  0.217  1.0
  Se  Se31  1  0.339  0.921  0.714  1.0
  Se  Se32  1  0.624  0.421  0.785  1.0
  Se  Se33  1  0.861  0.085  0.282  1.0
  Se  Se34  1  0.539  0.921  0.715  1.0
  Se  Se35  1  0.822  0.426  0.791  1.0
  Se  Se36  1  0.973  0.578  0.215  1.0
  Se  Se37  1  0.740  0.917  0.715  1.0
  Se  Se38  1  0.937  0.924  0.715  1.0
[/CIF]
.
The structure described by Ti20Se19 crystallizes in the triclinic P1 space group. There are twenty inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one Se(1), one Se(12), one Se(17), one Se(2), one Se(3), and one Se(5) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra, corners with two equivalent Ti(19)Se6 octahedra, corners with two equivalent Ti(5)Se6 octahedra, corners with two equivalent Ti(9)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(20)Se5 square pyramid,  an edgeedge with one Ti(15)Se5 trigonal bipyramid,  a faceface with one Ti(2)Se6 octahedra, and  a faceface with one Ti(4)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the second Ti site, Ti(2) is bonded to one Se(1), one Se(16), one Se(17), one Se(2), one Se(3), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra, corners with two equivalent Ti(10)Se6 octahedra, corners with two equivalent Ti(6)Se6 octahedra,  a cornercorner with one Ti(18)Se5 square pyramid, corners with two equivalent Ti(20)Se5 square pyramids,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(16)Se5 square pyramid,  an edgeedge with one Ti(17)Se5 square pyramid,  a faceface with one Ti(1)Se6 octahedra, and  a faceface with one Ti(15)Se5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 39-54°. In the third Ti site, Ti(3) is bonded to one Se(10), one Se(15), one Se(2), one Se(4), one Se(5), and one Se(6) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra, corners with two equivalent Ti(5)Se6 octahedra, corners with two equivalent Ti(9)Se6 octahedra,  a cornercorner with one Ti(17)Se5 square pyramid, corners with two equivalent Ti(13)Se5 square pyramids,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid,  a faceface with one Ti(4)Se6 octahedra, and  a faceface with one Ti(8)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the fourth Ti site, Ti(4) is bonded to one Se(12), one Se(2), one Se(3), one Se(4), one Se(5), and one Se(6) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(10)Se6 octahedra, corners with two equivalent Ti(14)Se6 octahedra, corners with two equivalent Ti(6)Se6 octahedra,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid,  a faceface with one Ti(1)Se6 octahedra, and  a faceface with one Ti(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 41-55°. In the fifth Ti site, Ti(5) is bonded to one Se(1), one Se(19), one Se(4), one Se(5), one Se(7), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(1)Se6 octahedra, corners with two equivalent Ti(3)Se6 octahedra,  a cornercorner with one Ti(20)Se5 square pyramid, corners with two equivalent Ti(15)Se5 trigonal bipyramids,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(16)Se5 square pyramid,  a faceface with one Ti(10)Se6 octahedra, and  a faceface with one Ti(6)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the sixth Ti site, Ti(6) is bonded to one Se(14), one Se(17), one Se(19), one Se(4), one Se(5), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(2)Se6 octahedra, corners with two equivalent Ti(4)Se6 octahedra,  a cornercorner with one Ti(17)Se5 square pyramid, corners with two equivalent Ti(16)Se5 square pyramids,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(20)Se5 square pyramid,  an edgeedge with one Ti(15)Se5 trigonal bipyramid,  a faceface with one Ti(19)Se6 octahedra, and  a faceface with one Ti(5)Se6 octahedra. The corner-sharing octahedral tilt angles range from 41-54°. In the seventh Ti site, Ti(7) is bonded to one Se(10), one Se(13), one Se(18), one Se(6), one Se(7), and one Se(9) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra, corners with two equivalent Ti(9)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid, corners with two equivalent Ti(13)Se5 square pyramids, corners with two equivalent Ti(17)Se5 square pyramids,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid,  an edgeedge with one Ti(20)Se5 square pyramid,  a faceface with one Ti(12)Se6 octahedra, and  a faceface with one Ti(8)Se6 octahedra. The corner-sharing octahedral tilt angles range from 41-54°. In the eighth Ti site, Ti(8) is bonded to one Se(10), one Se(15), one Se(5), one Se(6), one Se(7), and one Se(9) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(10)Se6 octahedra, corners with two equivalent Ti(14)Se6 octahedra,  a cornercorner with one Ti(20)Se5 square pyramid, corners with two equivalent Ti(18)Se5 square pyramids,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid,  an edgeedge with one Ti(17)Se5 square pyramid,  a faceface with one Ti(3)Se6 octahedra, and  a faceface with one Ti(7)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-54°. In the ninth Ti site, Ti(9) is bonded to one Se(10), one Se(11), one Se(12), one Se(2), one Se(7), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra, corners with two equivalent Ti(1)Se6 octahedra, corners with two equivalent Ti(3)Se6 octahedra, corners with two equivalent Ti(7)Se6 octahedra,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid,  a faceface with one Ti(10)Se6 octahedra, and  a faceface with one Ti(14)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-56°. In the tenth Ti site, Ti(10) is bonded to one Se(1), one Se(10), one Se(12), one Se(4), one Se(7), and one Se(8) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(2)Se6 octahedra, corners with two equivalent Ti(4)Se6 octahedra, corners with two equivalent Ti(8)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(15)Se5 trigonal bipyramid,  a faceface with one Ti(5)Se6 octahedra, and  a faceface with one Ti(9)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the eleventh Ti site, Ti(11) is bonded to one Se(11), one Se(13), one Se(14), one Se(16), one Se(19), and one Se(9) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(19)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid, corners with two equivalent Ti(13)Se5 square pyramids, corners with two equivalent Ti(17)Se5 square pyramids,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid,  an edgeedge with one Ti(20)Se5 square pyramid,  an edgeedge with one Ti(15)Se5 trigonal bipyramid,  a faceface with one Ti(12)Se6 octahedra, and  a faceface with one Ti(16)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 40-57°. In the twelfth Ti site, Ti(12) is bonded to one Se(10), one Se(11), one Se(13), one Se(14), one Se(18), and one Se(9) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(14)Se6 octahedra, corners with two equivalent Ti(18)Se5 square pyramids, corners with two equivalent Ti(20)Se5 square pyramids,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid,  an edgeedge with one Ti(16)Se5 square pyramid,  an edgeedge with one Ti(17)Se5 square pyramid,  a faceface with one Ti(11)Se6 octahedra, and  a faceface with one Ti(7)Se6 octahedra. The corner-sharing octahedral tilt angles range from 42-54°. In the thirteenth Ti site, Ti(13) is bonded to one Se(11), one Se(12), one Se(13), one Se(15), and one Se(6) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra, corners with two equivalent Ti(11)Se6 octahedra, corners with two equivalent Ti(3)Se6 octahedra, corners with two equivalent Ti(7)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  a cornercorner with one Ti(18)Se5 square pyramid,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(9)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid, and  a faceface with one Ti(14)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-54°. In the fourteenth Ti site, Ti(14) is bonded to one Se(11), one Se(12), one Se(13), one Se(15), one Se(2), and one Se(7) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(12)Se6 octahedra, corners with two equivalent Ti(4)Se6 octahedra, corners with two equivalent Ti(8)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(18)Se5 square pyramid,  a faceface with one Ti(9)Se6 octahedra, and  a faceface with one Ti(13)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 39-54°. In the fifteenth Ti site, Ti(15) is bonded to one Se(1), one Se(14), one Se(16), one Se(3), and one Se(8) atom to form distorted TiSe5 trigonal bipyramids that share  a cornercorner with one Ti(12)Se6 octahedra,  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(19)Se6 octahedra, corners with two equivalent Ti(5)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(10)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(16)Se5 square pyramid, and  a faceface with one Ti(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 40-54°. In the sixteenth Ti site, Ti(16) is bonded to one Se(1), one Se(13), one Se(14), one Se(16), and one Se(19) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(11)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(6)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(15)Se5 trigonal bipyramid, and  a faceface with one Ti(11)Se6 octahedra. The corner-sharing octahedral tilt angles range from 39-55°. In the seventeenth Ti site, Ti(17) is bonded to one Se(15), one Se(16), one Se(17), one Se(18), and one Se(9) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(1)Se6 octahedra,  a cornercorner with one Ti(14)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra, corners with two equivalent Ti(11)Se6 octahedra, corners with two equivalent Ti(7)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(19)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(8)Se6 octahedra,  an edgeedge with one Ti(20)Se5 square pyramid, and  a faceface with one Ti(18)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 40-54°. In the eighteenth Ti site, Ti(18) is bonded to one Se(11), one Se(15), one Se(16), one Se(18), and one Se(6) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(2)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(9)Se6 octahedra, corners with two equivalent Ti(12)Se6 octahedra, corners with two equivalent Ti(8)Se6 octahedra,  a cornercorner with one Ti(13)Se5 square pyramid,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(14)Se6 octahedra,  an edgeedge with one Ti(3)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(13)Se5 square pyramid, and  a faceface with one Ti(17)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 38-54°. In the nineteenth Ti site, Ti(19) is bonded to one Se(14), one Se(17), one Se(18), one Se(19), one Se(3), and one Se(4) atom to form distorted TiSe6 octahedra that share  a cornercorner with one Ti(10)Se6 octahedra,  a cornercorner with one Ti(3)Se6 octahedra,  a cornercorner with one Ti(6)Se6 octahedra,  a cornercorner with one Ti(7)Se6 octahedra, corners with two equivalent Ti(1)Se6 octahedra, corners with two equivalent Ti(11)Se6 octahedra,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(20)Se5 square pyramid, corners with two equivalent Ti(15)Se5 trigonal bipyramids,  an edgeedge with one Ti(12)Se6 octahedra,  an edgeedge with one Ti(2)Se6 octahedra,  an edgeedge with one Ti(4)Se6 octahedra,  an edgeedge with one Ti(5)Se6 octahedra,  an edgeedge with one Ti(16)Se5 square pyramid,  an edgeedge with one Ti(17)Se5 square pyramid,  a faceface with one Ti(6)Se6 octahedra, and  a faceface with one Ti(20)Se5 square pyramid. The corner-sharing octahedral tilt angles range from 40-57°. In the twentieth Ti site, Ti(20) is bonded to one Se(17), one Se(18), one Se(19), one Se(3), and one Se(9) atom to form distorted TiSe5 square pyramids that share  a cornercorner with one Ti(19)Se6 octahedra,  a cornercorner with one Ti(4)Se6 octahedra,  a cornercorner with one Ti(5)Se6 octahedra,  a cornercorner with one Ti(8)Se6 octahedra, corners with two equivalent Ti(12)Se6 octahedra, corners with two equivalent Ti(2)Se6 octahedra,  a cornercorner with one Ti(16)Se5 square pyramid,  a cornercorner with one Ti(17)Se5 square pyramid,  a cornercorner with one Ti(18)Se5 square pyramid,  a cornercorner with one Ti(15)Se5 trigonal bipyramid,  an edgeedge with one Ti(1)Se6 octahedra,  an edgeedge with one Ti(11)Se6 octahedra,  an edgeedge with one Ti(6)Se6 octahedra,  an edgeedge with one Ti(7)Se6 octahedra,  an edgeedge with one Ti(17)Se5 square pyramid, and  a faceface with one Ti(19)Se6 octahedra. The corner-sharing octahedral tilt angles range from 38-55°. There are nineteen inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(10), one Ti(15), one Ti(16), one Ti(2), and one Ti(5) atom. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(14), one Ti(2), one Ti(3), one Ti(4), and one Ti(9) atom. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(15), one Ti(19), one Ti(2), one Ti(20), and one Ti(4) atom. In the fourth Se site, Se(4) is bonded in a 6-coordinate geometry to one Ti(10), one Ti(19), one Ti(3), one Ti(4), one Ti(5), and one Ti(6) atom. In the fifth Se site, Se(5) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(3), one Ti(4), one Ti(5), one Ti(6), and one Ti(8) atom. In the sixth Se site, Se(6) is bonded in a 6-coordinate geometry to one Ti(13), one Ti(18), one Ti(3), one Ti(4), one Ti(7), and one Ti(8) atom. In the seventh Se site, Se(7) is bonded in a 6-coordinate geometry to one Ti(10), one Ti(14), one Ti(5), one Ti(7), one Ti(8), and one Ti(9) atom. In the eighth Se site, Se(8) is bonded in a 6-coordinate geometry to one Ti(10), one Ti(15), one Ti(2), one Ti(5), one Ti(6), and one Ti(9) atom. In the ninth Se site, Se(9) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(12), one Ti(17), one Ti(20), one Ti(7), and one Ti(8) atom. In the tenth Se site, Se(10) is bonded in a 6-coordinate geometry to one Ti(10), one Ti(12), one Ti(3), one Ti(7), one Ti(8), and one Ti(9) atom. In the eleventh Se site, Se(11) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(12), one Ti(13), one Ti(14), one Ti(18), and one Ti(9) atom. In the twelfth Se site, Se(12) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(10), one Ti(13), one Ti(14), one Ti(4), and one Ti(9) atom. In the thirteenth Se site, Se(13) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(12), one Ti(13), one Ti(14), one Ti(16), and one Ti(7) atom. In the fourteenth Se site, Se(14) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(12), one Ti(15), one Ti(16), one Ti(19), and one Ti(6) atom. In the fifteenth Se site, Se(15) is bonded in a 6-coordinate geometry to one Ti(13), one Ti(14), one Ti(17), one Ti(18), one Ti(3), and one Ti(8) atom. In the sixteenth Se site, Se(16) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(15), one Ti(16), one Ti(17), one Ti(18), and one Ti(2) atom. In the seventeenth Se site, Se(17) is bonded in a 6-coordinate geometry to one Ti(1), one Ti(17), one Ti(19), one Ti(2), one Ti(20), and one Ti(6) atom. In the eighteenth Se site, Se(18) is bonded in a 6-coordinate geometry to one Ti(12), one Ti(17), one Ti(18), one Ti(19), one Ti(20), and one Ti(7) atom. In the nineteenth Se site, Se(19) is bonded in a 6-coordinate geometry to one Ti(11), one Ti(16), one Ti(19), one Ti(20), one Ti(5), and one Ti(6) atom. is represented by the CIF card [CIF]
data_Ti20Se19
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   17.156
_cell_length_b   9.273
_cell_length_c   7.349
_cell_angle_alpha   69.766
_cell_angle_beta   62.185
_cell_angle_gamma   42.236
_symmetry_Int_Tables_number   1
_cell_volume   695.048
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ti  Ti0  1  0.172  0.193  0.005  1.0
  Ti  Ti1  1  0.025  0.307  0.508  1.0
  Ti  Ti2  1  0.372  0.192  0.007  1.0
  Ti  Ti3  1  0.226  0.305  0.507  1.0
  Ti  Ti4  1  0.172  0.696  0.494  1.0
  Ti  Ti5  1  0.028  0.806  0.994  1.0
  Ti  Ti6  1  0.573  0.190  0.006  1.0
  Ti  Ti7  1  0.428  0.305  0.507  1.0
  Ti  Ti8  1  0.375  0.693  0.493  1.0
  Ti  Ti9  1  0.229  0.807  0.994  1.0
  Ti  Ti10  1  0.771  0.192  0.006  1.0
  Ti  Ti11  1  0.627  0.303  0.507  1.0
  Ti  Ti12  1  0.575  0.693  0.495  1.0
  Ti  Ti13  1  0.431  0.804  0.993  1.0
  Ti  Ti14  1  0.970  0.200  0.001  1.0
  Ti  Ti15  1  0.826  0.311  0.505  1.0
  Ti  Ti16  1  0.772  0.693  0.494  1.0
  Ti  Ti17  1  0.630  0.803  0.990  1.0
  Ti  Ti18  1  0.972  0.695  0.492  1.0
  Ti  Ti19  1  0.831  0.803  0.990  1.0
  Se  Se20  1  0.059  0.085  0.281  1.0
  Se  Se21  1  0.262  0.077  0.285  1.0
  Se  Se22  1  0.020  0.426  0.789  1.0
  Se  Se23  1  0.175  0.579  0.215  1.0
  Se  Se24  1  0.224  0.422  0.784  1.0
  Se  Se25  1  0.464  0.074  0.284  1.0
  Se  Se26  1  0.376  0.577  0.216  1.0
  Se  Se27  1  0.137  0.923  0.717  1.0
  Se  Se28  1  0.664  0.073  0.283  1.0
  Se  Se29  1  0.424  0.421  0.786  1.0
  Se  Se30  1  0.579  0.577  0.217  1.0
  Se  Se31  1  0.339  0.921  0.714  1.0
  Se  Se32  1  0.624  0.421  0.785  1.0
  Se  Se33  1  0.861  0.085  0.282  1.0
  Se  Se34  1  0.539  0.921  0.715  1.0
  Se  Se35  1  0.822  0.426  0.791  1.0
  Se  Se36  1  0.973  0.578  0.215  1.0
  Se  Se37  1  0.740  0.917  0.715  1.0
  Se  Se38  1  0.937  0.924  0.715  1.0
[/CIF]
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