Ca7(TiS2)8 crystallizes in the trigonal P-3m1 space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to six equivalent S(1) atoms to form distorted CaS6 octahedra that share corners with twelve equivalent Ti(2)S6 octahedra, edges with six equivalent Ca(2)S6 octahedra, and faces with two equivalent Ti(1)S6 octahedra. The corner-sharing octahedral tilt angles are 51°. In the second Ca site, Ca(2) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form CaS6 octahedra that share corners with four equivalent Ti(1)S6 octahedra, corners with eight equivalent Ti(2)S6 octahedra, edges with two equivalent Ca(1)S6 octahedra, edges with four equivalent Ca(2)S6 octahedra, and faces with two equivalent Ti(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 44-46°. In the third Ca site, Ca(3) is bonded to two equivalent S(4) and four equivalent S(2) atoms to form distorted CaS6 octahedra that share corners with four equivalent Ti(1)S6 octahedra, corners with eight equivalent Ti(2)S6 octahedra, edges with four equivalent Ca(3)S6 octahedra, and faces with two equivalent Ti(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 47-50°. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent S(1) and three equivalent S(2) atoms to form TiS6 octahedra that share corners with six equivalent Ca(2)S6 octahedra, corners with six equivalent Ca(3)S6 octahedra, edges with six equivalent Ti(2)S6 octahedra, and  a faceface with one Ca(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 46-47°. In the second Ti site, Ti(2) is bonded to one S(3), one S(4), two equivalent S(1), and two equivalent S(2) atoms to form TiS6 octahedra that share corners with two equivalent Ca(1)S6 octahedra, corners with four equivalent Ca(2)S6 octahedra, corners with four equivalent Ca(3)S6 octahedra, edges with two equivalent Ti(1)S6 octahedra, edges with four equivalent Ti(2)S6 octahedra,  a faceface with one Ca(2)S6 octahedra, and  a faceface with one Ca(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 44-51°. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 6-coordinate geometry to one Ca(1), two equivalent Ca(2), one Ti(1), and two equivalent Ti(2) atoms. In the second S site, S(2) is bonded to two equivalent Ca(3), one Ti(1), and two equivalent Ti(2) atoms to form distorted SCa2Ti3 trigonal bipyramids that share corners with six equivalent S(2)Ca2Ti3 trigonal bipyramids,  an edgeedge with one S(3)Ca3Ti3 pentagonal pyramid, and edges with two equivalent S(2)Ca2Ti3 trigonal bipyramids. In the third S site, S(3) is bonded to three equivalent Ca(2) and three equivalent Ti(2) atoms to form distorted SCa3Ti3 pentagonal pyramids that share corners with three equivalent S(3)Ca3Ti3 pentagonal pyramids and edges with three equivalent S(2)Ca2Ti3 trigonal bipyramids. In the fourth S site, S(4) is bonded in a 6-coordinate geometry to three equivalent Ca(3) and three equivalent Ti(2) atoms.
Ca7(TiS2)8 crystallizes in the trigonal P-3m1 space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to six equivalent S(1) atoms to form distorted CaS6 octahedra that share corners with twelve equivalent Ti(2)S6 octahedra, edges with six equivalent Ca(2)S6 octahedra, and faces with two equivalent Ti(1)S6 octahedra. The corner-sharing octahedral tilt angles are 51°. All Ca(1)-S(1) bond lengths are 2.81 Å. In the second Ca site, Ca(2) is bonded to two equivalent S(3) and four equivalent S(1) atoms to form CaS6 octahedra that share corners with four equivalent Ti(1)S6 octahedra, corners with eight equivalent Ti(2)S6 octahedra, edges with two equivalent Ca(1)S6 octahedra, edges with four equivalent Ca(2)S6 octahedra, and faces with two equivalent Ti(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 44-46°. Both Ca(2)-S(3) bond lengths are 2.71 Å. All Ca(2)-S(1) bond lengths are 2.81 Å. In the third Ca site, Ca(3) is bonded to two equivalent S(4) and four equivalent S(2) atoms to form distorted CaS6 octahedra that share corners with four equivalent Ti(1)S6 octahedra, corners with eight equivalent Ti(2)S6 octahedra, edges with four equivalent Ca(3)S6 octahedra, and faces with two equivalent Ti(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 47-50°. Both Ca(3)-S(4) bond lengths are 2.85 Å. All Ca(3)-S(2) bond lengths are 2.78 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent S(1) and three equivalent S(2) atoms to form TiS6 octahedra that share corners with six equivalent Ca(2)S6 octahedra, corners with six equivalent Ca(3)S6 octahedra, edges with six equivalent Ti(2)S6 octahedra, and  a faceface with one Ca(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 46-47°. All Ti(1)-S(1) bond lengths are 2.55 Å. All Ti(1)-S(2) bond lengths are 2.53 Å. In the second Ti site, Ti(2) is bonded to one S(3), one S(4), two equivalent S(1), and two equivalent S(2) atoms to form TiS6 octahedra that share corners with two equivalent Ca(1)S6 octahedra, corners with four equivalent Ca(2)S6 octahedra, corners with four equivalent Ca(3)S6 octahedra, edges with two equivalent Ti(1)S6 octahedra, edges with four equivalent Ti(2)S6 octahedra,  a faceface with one Ca(2)S6 octahedra, and  a faceface with one Ca(3)S6 octahedra. The corner-sharing octahedral tilt angles range from 44-51°. The Ti(2)-S(3) bond length is 2.43 Å. The Ti(2)-S(4) bond length is 2.69 Å. Both Ti(2)-S(1) bond lengths are 2.63 Å. Both Ti(2)-S(2) bond lengths are 2.46 Å. There are four inequivalent S sites. In the first S site, S(1) is bonded in a 6-coordinate geometry to one Ca(1), two equivalent Ca(2), one Ti(1), and two equivalent Ti(2) atoms. In the second S site, S(2) is bonded to two equivalent Ca(3), one Ti(1), and two equivalent Ti(2) atoms to form distorted SCa2Ti3 trigonal bipyramids that share corners with six equivalent S(2)Ca2Ti3 trigonal bipyramids,  an edgeedge with one S(3)Ca3Ti3 pentagonal pyramid, and edges with two equivalent S(2)Ca2Ti3 trigonal bipyramids. In the third S site, S(3) is bonded to three equivalent Ca(2) and three equivalent Ti(2) atoms to form distorted SCa3Ti3 pentagonal pyramids that share corners with three equivalent S(3)Ca3Ti3 pentagonal pyramids and edges with three equivalent S(2)Ca2Ti3 trigonal bipyramids. In the fourth S site, S(4) is bonded in a 6-coordinate geometry to three equivalent Ca(3) and three equivalent Ti(2) atoms.