The material described by Ca3Er2Sn3S12 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to one S(3), two equivalent S(4), two equivalent S(5), two equivalent S(6), and two equivalent S(7) atoms. In the second Ca site, Ca(2) is bonded to one S(3), two equivalent S(2), and four equivalent S(7) atoms to form distorted CaS7 pentagonal bipyramids that share corners with two equivalent Sn(1)S6 octahedra, corners with two equivalent Er(1)S7 pentagonal bipyramids, edges with four equivalent Sn(2)S6 octahedra, and edges with two equivalent Ca(2)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 50°. Er(1) is bonded to one S(1), one S(2), one S(4), two equivalent S(5), and two equivalent S(6) atoms to form distorted ErS7 pentagonal bipyramids that share corners with two equivalent Sn(2)S6 octahedra,  a cornercorner with one Ca(2)S7 pentagonal bipyramid,  a cornercorner with one Er(1)S7 pentagonal bipyramid, edges with two equivalent Sn(1)S6 octahedra, edges with two equivalent Sn(2)S6 octahedra, and edges with two equivalent Er(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 49°. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to two equivalent S(1), two equivalent S(3), and two equivalent S(5) atoms to form SnS6 octahedra that share corners with two equivalent Ca(2)S7 pentagonal bipyramids, edges with two equivalent Sn(1)S6 octahedra, and edges with four equivalent Er(1)S7 pentagonal bipyramids. In the second Sn site, Sn(2) is bonded to one S(6), one S(7), two equivalent S(2), and two equivalent S(4) atoms to form SnS6 octahedra that share corners with two equivalent Er(1)S7 pentagonal bipyramids, edges with two equivalent Sn(2)S6 octahedra, edges with two equivalent Ca(2)S7 pentagonal bipyramids, and edges with two equivalent Er(1)S7 pentagonal bipyramids. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to two equivalent Er(1) and two equivalent Sn(1) atoms. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Er(1), and two equivalent Sn(2) atoms. In the third S site, S(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent Sn(1) atoms to form distorted SCa3Sn2 trigonal bipyramids that share corners with two equivalent S(3)Ca3Sn2 trigonal bipyramids, corners with four equivalent S(6)Ca2Er2Sn trigonal bipyramids, corners with four equivalent S(4)Ca2ErSn2 trigonal bipyramids, edges with four equivalent S(5)Ca2Er2Sn square pyramids, and edges with four equivalent S(7)Ca4Sn square pyramids. In the fourth S site, S(4) is bonded to two equivalent Ca(1), one Er(1), and two equivalent Sn(2) atoms to form distorted SCa2ErSn2 trigonal bipyramids that share corners with two equivalent S(5)Ca2Er2Sn square pyramids, corners with two equivalent S(7)Ca4Sn square pyramids, corners with two equivalent S(3)Ca3Sn2 trigonal bipyramids, corners with four equivalent S(4)Ca2ErSn2 trigonal bipyramids, edges with two equivalent S(5)Ca2Er2Sn square pyramids, edges with two equivalent S(7)Ca4Sn square pyramids, and edges with four equivalent S(6)Ca2Er2Sn trigonal bipyramids. In the fifth S site, S(5) is bonded to two equivalent Ca(1), two equivalent Er(1), and one Sn(1) atom to form SCa2Er2Sn square pyramids that share  a cornercorner with one S(5)Ca2Er2Sn square pyramid, corners with two equivalent S(7)Ca4Sn square pyramids, corners with two equivalent S(4)Ca2ErSn2 trigonal bipyramids, corners with four equivalent S(6)Ca2Er2Sn trigonal bipyramids,  an edgeedge with one S(7)Ca4Sn square pyramid, edges with two equivalent S(5)Ca2Er2Sn square pyramids, edges with two equivalent S(6)Ca2Er2Sn trigonal bipyramids, edges with two equivalent S(4)Ca2ErSn2 trigonal bipyramids, and edges with two equivalent S(3)Ca3Sn2 trigonal bipyramids. In the sixth S site, S(6) is bonded to two equivalent Ca(1), two equivalent Er(1), and one Sn(2) atom to form SCa2Er2Sn trigonal bipyramids that share corners with three equivalent S(7)Ca4Sn square pyramids, corners with four equivalent S(5)Ca2Er2Sn square pyramids, corners with two equivalent S(3)Ca3Sn2 trigonal bipyramids,  an edgeedge with one S(7)Ca4Sn square pyramid, edges with two equivalent S(5)Ca2Er2Sn square pyramids, edges with two equivalent S(6)Ca2Er2Sn trigonal bipyramids, and edges with four equivalent S(4)Ca2ErSn2 trigonal bipyramids. In the seventh S site, S(7) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Sn(2) atom to form SCa4Sn square pyramids that share corners with two equivalent S(5)Ca2Er2Sn square pyramids, corners with two equivalent S(7)Ca4Sn square pyramids, corners with two equivalent S(4)Ca2ErSn2 trigonal bipyramids, corners with three equivalent S(6)Ca2Er2Sn trigonal bipyramids,  an edgeedge with one S(5)Ca2Er2Sn square pyramid, edges with three equivalent S(7)Ca4Sn square pyramids,  an edgeedge with one S(6)Ca2Er2Sn trigonal bipyramid, edges with two equivalent S(4)Ca2ErSn2 trigonal bipyramids, and edges with two equivalent S(3)Ca3Sn2 trigonal bipyramids. is represented by the CIF card [CIF]
data_Ca3Er2(SnS4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.555
_cell_length_b   11.555
_cell_length_c   3.903
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.523
_symmetry_Int_Tables_number   1
_cell_volume   448.929
_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
  Ca  Ca0  1  0.662  0.330  0.000  1.0
  Ca  Ca1  1  0.330  0.662  0.000  1.0
  Ca  Ca2  1  0.283  0.283  0.000  1.0
  Er  Er3  1  0.001  0.715  0.000  1.0
  Er  Er4  1  0.715  0.001  0.000  1.0
  Sn  Sn5  1  0.672  0.672  0.500  1.0
  Sn  Sn6  1  0.003  0.329  0.500  1.0
  Sn  Sn7  1  0.329  0.003  0.500  1.0
  S  S8  1  0.827  0.827  0.000  1.0
  S  S9  1  0.992  0.171  0.000  1.0
  S  S10  1  0.171  0.992  0.000  1.0
  S  S11  1  0.528  0.528  0.000  1.0
  S  S12  1  0.997  0.474  0.000  1.0
  S  S13  1  0.474  0.997  0.000  1.0
  S  S14  1  0.815  0.562  0.500  1.0
  S  S15  1  0.746  0.187  0.500  1.0
  S  S16  1  0.450  0.254  0.500  1.0
  S  S17  1  0.562  0.815  0.500  1.0
  S  S18  1  0.187  0.746  0.500  1.0
  S  S19  1  0.254  0.450  0.500  1.0
[/CIF]
.
The material described by Ca3Er2Sn3S12 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to one S(3), two equivalent S(4), two equivalent S(5), two equivalent S(6), and two equivalent S(7) atoms. In the second Ca site, Ca(2) is bonded to one S(3), two equivalent S(2), and four equivalent S(7) atoms to form distorted CaS7 pentagonal bipyramids that share corners with two equivalent Sn(1)S6 octahedra, corners with two equivalent Er(1)S7 pentagonal bipyramids, edges with four equivalent Sn(2)S6 octahedra, and edges with two equivalent Ca(2)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 50°. Er(1) is bonded to one S(1), one S(2), one S(4), two equivalent S(5), and two equivalent S(6) atoms to form distorted ErS7 pentagonal bipyramids that share corners with two equivalent Sn(2)S6 octahedra,  a cornercorner with one Ca(2)S7 pentagonal bipyramid,  a cornercorner with one Er(1)S7 pentagonal bipyramid, edges with two equivalent Sn(1)S6 octahedra, edges with two equivalent Sn(2)S6 octahedra, and edges with two equivalent Er(1)S7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 49°. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to two equivalent S(1), two equivalent S(3), and two equivalent S(5) atoms to form SnS6 octahedra that share corners with two equivalent Ca(2)S7 pentagonal bipyramids, edges with two equivalent Sn(1)S6 octahedra, and edges with four equivalent Er(1)S7 pentagonal bipyramids. In the second Sn site, Sn(2) is bonded to one S(6), one S(7), two equivalent S(2), and two equivalent S(4) atoms to form SnS6 octahedra that share corners with two equivalent Er(1)S7 pentagonal bipyramids, edges with two equivalent Sn(2)S6 octahedra, edges with two equivalent Ca(2)S7 pentagonal bipyramids, and edges with two equivalent Er(1)S7 pentagonal bipyramids. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to two equivalent Er(1) and two equivalent Sn(1) atoms. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to one Ca(2), one Er(1), and two equivalent Sn(2) atoms. In the third S site, S(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent Sn(1) atoms to form distorted SCa3Sn2 trigonal bipyramids that share corners with two equivalent S(3)Ca3Sn2 trigonal bipyramids, corners with four equivalent S(6)Ca2Er2Sn trigonal bipyramids, corners with four equivalent S(4)Ca2ErSn2 trigonal bipyramids, edges with four equivalent S(5)Ca2Er2Sn square pyramids, and edges with four equivalent S(7)Ca4Sn square pyramids. In the fourth S site, S(4) is bonded to two equivalent Ca(1), one Er(1), and two equivalent Sn(2) atoms to form distorted SCa2ErSn2 trigonal bipyramids that share corners with two equivalent S(5)Ca2Er2Sn square pyramids, corners with two equivalent S(7)Ca4Sn square pyramids, corners with two equivalent S(3)Ca3Sn2 trigonal bipyramids, corners with four equivalent S(4)Ca2ErSn2 trigonal bipyramids, edges with two equivalent S(5)Ca2Er2Sn square pyramids, edges with two equivalent S(7)Ca4Sn square pyramids, and edges with four equivalent S(6)Ca2Er2Sn trigonal bipyramids. In the fifth S site, S(5) is bonded to two equivalent Ca(1), two equivalent Er(1), and one Sn(1) atom to form SCa2Er2Sn square pyramids that share  a cornercorner with one S(5)Ca2Er2Sn square pyramid, corners with two equivalent S(7)Ca4Sn square pyramids, corners with two equivalent S(4)Ca2ErSn2 trigonal bipyramids, corners with four equivalent S(6)Ca2Er2Sn trigonal bipyramids,  an edgeedge with one S(7)Ca4Sn square pyramid, edges with two equivalent S(5)Ca2Er2Sn square pyramids, edges with two equivalent S(6)Ca2Er2Sn trigonal bipyramids, edges with two equivalent S(4)Ca2ErSn2 trigonal bipyramids, and edges with two equivalent S(3)Ca3Sn2 trigonal bipyramids. In the sixth S site, S(6) is bonded to two equivalent Ca(1), two equivalent Er(1), and one Sn(2) atom to form SCa2Er2Sn trigonal bipyramids that share corners with three equivalent S(7)Ca4Sn square pyramids, corners with four equivalent S(5)Ca2Er2Sn square pyramids, corners with two equivalent S(3)Ca3Sn2 trigonal bipyramids,  an edgeedge with one S(7)Ca4Sn square pyramid, edges with two equivalent S(5)Ca2Er2Sn square pyramids, edges with two equivalent S(6)Ca2Er2Sn trigonal bipyramids, and edges with four equivalent S(4)Ca2ErSn2 trigonal bipyramids. In the seventh S site, S(7) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Sn(2) atom to form SCa4Sn square pyramids that share corners with two equivalent S(5)Ca2Er2Sn square pyramids, corners with two equivalent S(7)Ca4Sn square pyramids, corners with two equivalent S(4)Ca2ErSn2 trigonal bipyramids, corners with three equivalent S(6)Ca2Er2Sn trigonal bipyramids,  an edgeedge with one S(5)Ca2Er2Sn square pyramid, edges with three equivalent S(7)Ca4Sn square pyramids,  an edgeedge with one S(6)Ca2Er2Sn trigonal bipyramid, edges with two equivalent S(4)Ca2ErSn2 trigonal bipyramids, and edges with two equivalent S(3)Ca3Sn2 trigonal bipyramids. is represented by the CIF card [CIF]
data_Ca3Er2(SnS4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.555
_cell_length_b   11.555
_cell_length_c   3.903
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.523
_symmetry_Int_Tables_number   1
_cell_volume   448.929
_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
  Ca  Ca0  1  0.662  0.330  0.000  1.0
  Ca  Ca1  1  0.330  0.662  0.000  1.0
  Ca  Ca2  1  0.283  0.283  0.000  1.0
  Er  Er3  1  0.001  0.715  0.000  1.0
  Er  Er4  1  0.715  0.001  0.000  1.0
  Sn  Sn5  1  0.672  0.672  0.500  1.0
  Sn  Sn6  1  0.003  0.329  0.500  1.0
  Sn  Sn7  1  0.329  0.003  0.500  1.0
  S  S8  1  0.827  0.827  0.000  1.0
  S  S9  1  0.992  0.171  0.000  1.0
  S  S10  1  0.171  0.992  0.000  1.0
  S  S11  1  0.528  0.528  0.000  1.0
  S  S12  1  0.997  0.474  0.000  1.0
  S  S13  1  0.474  0.997  0.000  1.0
  S  S14  1  0.815  0.562  0.500  1.0
  S  S15  1  0.746  0.187  0.500  1.0
  S  S16  1  0.450  0.254  0.500  1.0
  S  S17  1  0.562  0.815  0.500  1.0
  S  S18  1  0.187  0.746  0.500  1.0
  S  S19  1  0.254  0.450  0.500  1.0
[/CIF]
.