Y6Al2SiS14 crystallizes in the trigonal P3 space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one S(1), one S(4), one S(6), two equivalent S(3), and two equivalent S(5) atoms. In the second Y site, Y(2) is bonded in a 8-coordinate geometry to one S(2), one S(3), two equivalent S(4), two equivalent S(5), and two equivalent S(6) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in an octahedral geometry to three equivalent S(5) and three equivalent S(6) atoms. In the second Al site, Al(2) is bonded in a tetrahedral geometry to one S(2) and three equivalent S(4) atoms. Si(1) is bonded in a tetrahedral geometry to one S(1) and three equivalent S(3) atoms. There are six inequivalent S sites. In the first S site, S(1) is bonded to three equivalent Y(1) and one Si(1) atom to form distorted corner-sharing SY3Si tetrahedra. In the second S site, S(2) is bonded to three equivalent Y(2) and one Al(2) atom to form distorted corner-sharing SY3Al tetrahedra. In the third S site, S(3) is bonded in a distorted rectangular see-saw-like geometry to one Y(2), two equivalent Y(1), and one Si(1) atom. In the fourth S site, S(4) is bonded in a distorted rectangular see-saw-like geometry to one Y(1), two equivalent Y(2), and one Al(2) atom. In the fifth S site, S(5) is bonded in a 4-coordinate geometry to two equivalent Y(1), two equivalent Y(2), and one Al(1) atom. In the sixth S site, S(6) is bonded to one Y(1), two equivalent Y(2), and one Al(1) atom to form distorted SY3Al trigonal pyramids that share  a cornercorner with one S(1)Y3Si tetrahedra, corners with two equivalent S(2)Y3Al tetrahedra, and edges with two equivalent S(6)Y3Al trigonal pyramids.
Y6Al2SiS14 crystallizes in the trigonal P3 space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one S(1), one S(4), one S(6), two equivalent S(3), and two equivalent S(5) atoms. The Y(1)-S(1) bond length is 2.86 Å. The Y(1)-S(4) bond length is 2.97 Å. The Y(1)-S(6) bond length is 2.69 Å. There is one shorter (2.81 Å) and one longer (2.87 Å) Y(1)-S(3) bond length. There is one shorter (2.74 Å) and one longer (2.79 Å) Y(1)-S(5) bond length. In the second Y site, Y(2) is bonded in a 8-coordinate geometry to one S(2), one S(3), two equivalent S(4), two equivalent S(5), and two equivalent S(6) atoms. The Y(2)-S(2) bond length is 2.83 Å. The Y(2)-S(3) bond length is 3.09 Å. There is one shorter (2.77 Å) and one longer (2.82 Å) Y(2)-S(4) bond length. There is one shorter (2.92 Å) and one longer (3.41 Å) Y(2)-S(5) bond length. There is one shorter (2.74 Å) and one longer (2.81 Å) Y(2)-S(6) bond length. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in an octahedral geometry to three equivalent S(5) and three equivalent S(6) atoms. All Al(1)-S(5) bond lengths are 2.49 Å. All Al(1)-S(6) bond lengths are 2.42 Å. In the second Al site, Al(2) is bonded in a tetrahedral geometry to one S(2) and three equivalent S(4) atoms. The Al(2)-S(2) bond length is 2.23 Å. All Al(2)-S(4) bond lengths are 2.26 Å. Si(1) is bonded in a tetrahedral geometry to one S(1) and three equivalent S(3) atoms. The Si(1)-S(1) bond length is 2.14 Å. All Si(1)-S(3) bond lengths are 2.14 Å. There are six inequivalent S sites. In the first S site, S(1) is bonded to three equivalent Y(1) and one Si(1) atom to form distorted corner-sharing SY3Si tetrahedra. In the second S site, S(2) is bonded to three equivalent Y(2) and one Al(2) atom to form distorted corner-sharing SY3Al tetrahedra. In the third S site, S(3) is bonded in a distorted rectangular see-saw-like geometry to one Y(2), two equivalent Y(1), and one Si(1) atom. In the fourth S site, S(4) is bonded in a distorted rectangular see-saw-like geometry to one Y(1), two equivalent Y(2), and one Al(2) atom. In the fifth S site, S(5) is bonded in a 4-coordinate geometry to two equivalent Y(1), two equivalent Y(2), and one Al(1) atom. In the sixth S site, S(6) is bonded to one Y(1), two equivalent Y(2), and one Al(1) atom to form distorted SY3Al trigonal pyramids that share  a cornercorner with one S(1)Y3Si tetrahedra, corners with two equivalent S(2)Y3Al tetrahedra, and edges with two equivalent S(6)Y3Al trigonal pyramids.