The material structure described by Ca10Si3S3(O12Cl)2 crystallizes in the monoclinic Pm space group. There are eight inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to one O(14), two equivalent O(1), two equivalent O(9), and two equivalent Cl(1) atoms. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(17), one O(7), two equivalent O(18), two equivalent O(4), and two equivalent Cl(1) atoms. In the third Ca site, Ca(3) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the fourth Ca site, Ca(4) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(4), two equivalent O(9), and two equivalent Cl(1) atoms. In the fifth Ca site, Ca(5) is bonded in a 8-coordinate geometry to one O(11), one O(6), two equivalent O(10), two equivalent O(15), and two equivalent Cl(1) atoms. In the sixth Ca site, Ca(6) is bonded in a 9-coordinate geometry to one O(11), one O(12), one O(13), one O(14), one O(15), one O(16), one O(17), one O(18), and one O(9) atom. In the seventh Ca site, Ca(7) is bonded in a 7-coordinate geometry to one O(2), two equivalent O(1), two equivalent O(15), and two equivalent Cl(1) atoms. In the eighth Ca site, Ca(8) is bonded in a 3-coordinate geometry to one O(16), one O(5), two equivalent O(18), and two equivalent Cl(1) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a tetrahedral geometry to one O(16), one O(2), and two equivalent O(4) atoms. In the second Si site, Si(2) is bonded in a tetrahedral geometry to one O(13), one O(5), and two equivalent O(1) atoms. In the third Si site, Si(3) is bonded in a tetrahedral geometry to one O(11), one O(7), and two equivalent O(9) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded in a tetrahedral geometry to one O(12), one O(8), and two equivalent O(10) atoms. In the second S site, S(2) is bonded in a tetrahedral geometry to one O(14), one O(6), and two equivalent O(18) atoms. In the third S site, S(3) is bonded in a tetrahedral geometry to one O(17), one O(3), and two equivalent O(15) atoms. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Ca(3), one Ca(7), and one Si(2) atom. In the second O site, O(2) is bonded to one Ca(7), two equivalent Ca(3), and one Si(1) atom to form distorted OCa3Si tetrahedra that share corners with two equivalent Cl(1)Ca6 octahedra and  an edgeedge with one O(5)Ca3Si tetrahedra. The corner-sharing octahedral tilt angles are 36°. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Ca(3) and one S(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(3), one Ca(4), and one Si(1) atom. In the fifth O site, O(5) is bonded to one Ca(8), two equivalent Ca(3), and one Si(2) atom to form distorted OCa3Si tetrahedra that share corners with two equivalent Cl(1)Ca6 octahedra and  an edgeedge with one O(2)Ca3Si tetrahedra. The corner-sharing octahedral tilt angles are 52°. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Ca(5), two equivalent Ca(3), and one S(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ca(2), two equivalent Ca(3), and one Si(3) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ca(4), two equivalent Ca(3), and one S(1) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(4), one Ca(6), and one Si(3) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Ca(5) and one S(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Ca(5), two equivalent Ca(6), and one Si(3) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to two equivalent Ca(6) and one S(1) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to two equivalent Ca(6) and one Si(2) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Ca(6), and one S(2) atom. In the fifteenth O site, O(15) is bonded in a 1-coordinate geometry to one Ca(5), one Ca(6), one Ca(7), and one S(3) atom. In the sixteenth O site, O(16) is bonded in a 4-coordinate geometry to one Ca(8), two equivalent Ca(6), and one Si(1) atom. In the seventeenth O site, O(17) is bonded to one Ca(2), two equivalent Ca(6), and one S(3) atom to form distorted OCa3S tetrahedra that share corners with two equivalent Cl(1)Ca6 octahedra. The corner-sharing octahedral tilt angles are 53°. In the eighteenth O site, O(18) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(6), one Ca(8), and one S(2) atom. Cl(1) is bonded to one Ca(1), one Ca(2), one Ca(4), one Ca(5), one Ca(7), and one Ca(8) atom to form ClCa6 octahedra that share  a cornercorner with one O(17)Ca3S tetrahedra,  a cornercorner with one O(2)Ca3Si tetrahedra,  a cornercorner with one O(5)Ca3Si tetrahedra, and faces with two equivalent Cl(1)Ca6 octahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca10Si3S3(ClO12)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.828
_cell_length_b   9.774
_cell_length_c   9.845
_cell_angle_alpha   60.684
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   572.919
_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  0.000  0.028  0.739  1.0
  Ca  Ca1  1  0.000  0.274  0.961  1.0
  Ca  Ca2  1  0.255  0.661  0.686  1.0
  Ca  Ca3  1  0.745  0.661  0.686  1.0
  Ca  Ca4  1  0.500  0.260  0.755  1.0
  Ca  Ca5  1  0.000  0.733  0.254  1.0
  Ca  Ca6  1  0.740  0.325  0.354  1.0
  Ca  Ca7  1  0.260  0.325  0.354  1.0
  Ca  Ca8  1  0.500  0.774  0.960  1.0
  Ca  Ca9  1  0.500  0.019  0.268  1.0
  Si  Si10  1  0.500  0.403  0.975  1.0
  Si  Si11  1  0.500  0.963  0.621  1.0
  Si  Si12  1  0.000  0.386  0.587  1.0
  S  S13  1  0.500  0.630  0.404  1.0
  S  S14  1  0.000  0.031  0.375  1.0
  S  S15  1  0.000  0.581  0.041  1.0
  Cl  Cl16  1  0.247  0.992  0.012  1.0
  Cl  Cl17  1  0.753  0.992  0.012  1.0
  O  O18  1  0.304  0.906  0.735  1.0
  O  O19  1  0.696  0.906  0.735  1.0
  O  O20  1  0.500  0.598  0.879  1.0
  O  O21  1  0.000  0.636  0.871  1.0
  O  O22  1  0.691  0.357  0.904  1.0
  O  O23  1  0.309  0.357  0.904  1.0
  O  O24  1  0.500  0.858  0.530  1.0
  O  O25  1  0.000  0.859  0.482  1.0
  O  O26  1  0.000  0.513  0.651  1.0
  O  O27  1  0.500  0.542  0.578  1.0
  O  O28  1  0.193  0.268  0.642  1.0
  O  O29  1  0.807  0.268  0.642  1.0
  O  O30  1  0.677  0.731  0.349  1.0
  O  O31  1  0.323  0.731  0.349  1.0
  O  O32  1  0.000  0.472  0.393  1.0
  O  O33  1  0.500  0.517  0.342  1.0
  O  O34  1  0.500  0.150  0.493  1.0
  O  O35  1  0.000  0.119  0.465  1.0
  O  O36  1  0.176  0.639  0.086  1.0
  O  O37  1  0.824  0.639  0.086  1.0
  O  O38  1  0.500  0.323  0.166  1.0
  O  O39  1  0.000  0.405  0.129  1.0
  O  O40  1  0.175  0.082  0.273  1.0
  O  O41  1  0.825  0.082  0.273  1.0
[/CIF]
.
The material structure described by Ca10Si3S3(O12Cl)2 crystallizes in the monoclinic Pm space group. There are eight inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to one O(14), two equivalent O(1), two equivalent O(9), and two equivalent Cl(1) atoms. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(17), one O(7), two equivalent O(18), two equivalent O(4), and two equivalent Cl(1) atoms. In the third Ca site, Ca(3) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the fourth Ca site, Ca(4) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(4), two equivalent O(9), and two equivalent Cl(1) atoms. In the fifth Ca site, Ca(5) is bonded in a 8-coordinate geometry to one O(11), one O(6), two equivalent O(10), two equivalent O(15), and two equivalent Cl(1) atoms. In the sixth Ca site, Ca(6) is bonded in a 9-coordinate geometry to one O(11), one O(12), one O(13), one O(14), one O(15), one O(16), one O(17), one O(18), and one O(9) atom. In the seventh Ca site, Ca(7) is bonded in a 7-coordinate geometry to one O(2), two equivalent O(1), two equivalent O(15), and two equivalent Cl(1) atoms. In the eighth Ca site, Ca(8) is bonded in a 3-coordinate geometry to one O(16), one O(5), two equivalent O(18), and two equivalent Cl(1) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a tetrahedral geometry to one O(16), one O(2), and two equivalent O(4) atoms. In the second Si site, Si(2) is bonded in a tetrahedral geometry to one O(13), one O(5), and two equivalent O(1) atoms. In the third Si site, Si(3) is bonded in a tetrahedral geometry to one O(11), one O(7), and two equivalent O(9) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded in a tetrahedral geometry to one O(12), one O(8), and two equivalent O(10) atoms. In the second S site, S(2) is bonded in a tetrahedral geometry to one O(14), one O(6), and two equivalent O(18) atoms. In the third S site, S(3) is bonded in a tetrahedral geometry to one O(17), one O(3), and two equivalent O(15) atoms. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Ca(3), one Ca(7), and one Si(2) atom. In the second O site, O(2) is bonded to one Ca(7), two equivalent Ca(3), and one Si(1) atom to form distorted OCa3Si tetrahedra that share corners with two equivalent Cl(1)Ca6 octahedra and  an edgeedge with one O(5)Ca3Si tetrahedra. The corner-sharing octahedral tilt angles are 36°. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Ca(3) and one S(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(3), one Ca(4), and one Si(1) atom. In the fifth O site, O(5) is bonded to one Ca(8), two equivalent Ca(3), and one Si(2) atom to form distorted OCa3Si tetrahedra that share corners with two equivalent Cl(1)Ca6 octahedra and  an edgeedge with one O(2)Ca3Si tetrahedra. The corner-sharing octahedral tilt angles are 52°. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Ca(5), two equivalent Ca(3), and one S(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ca(2), two equivalent Ca(3), and one Si(3) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ca(4), two equivalent Ca(3), and one S(1) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(4), one Ca(6), and one Si(3) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Ca(5) and one S(1) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one Ca(5), two equivalent Ca(6), and one Si(3) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to two equivalent Ca(6) and one S(1) atom. In the thirteenth O site, O(13) is bonded in a 3-coordinate geometry to two equivalent Ca(6) and one Si(2) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Ca(6), and one S(2) atom. In the fifteenth O site, O(15) is bonded in a 1-coordinate geometry to one Ca(5), one Ca(6), one Ca(7), and one S(3) atom. In the sixteenth O site, O(16) is bonded in a 4-coordinate geometry to one Ca(8), two equivalent Ca(6), and one Si(1) atom. In the seventeenth O site, O(17) is bonded to one Ca(2), two equivalent Ca(6), and one S(3) atom to form distorted OCa3S tetrahedra that share corners with two equivalent Cl(1)Ca6 octahedra. The corner-sharing octahedral tilt angles are 53°. In the eighteenth O site, O(18) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(6), one Ca(8), and one S(2) atom. Cl(1) is bonded to one Ca(1), one Ca(2), one Ca(4), one Ca(5), one Ca(7), and one Ca(8) atom to form ClCa6 octahedra that share  a cornercorner with one O(17)Ca3S tetrahedra,  a cornercorner with one O(2)Ca3Si tetrahedra,  a cornercorner with one O(5)Ca3Si tetrahedra, and faces with two equivalent Cl(1)Ca6 octahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca10Si3S3(ClO12)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.828
_cell_length_b   9.774
_cell_length_c   9.845
_cell_angle_alpha   60.684
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   572.919
_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  0.000  0.028  0.739  1.0
  Ca  Ca1  1  0.000  0.274  0.961  1.0
  Ca  Ca2  1  0.255  0.661  0.686  1.0
  Ca  Ca3  1  0.745  0.661  0.686  1.0
  Ca  Ca4  1  0.500  0.260  0.755  1.0
  Ca  Ca5  1  0.000  0.733  0.254  1.0
  Ca  Ca6  1  0.740  0.325  0.354  1.0
  Ca  Ca7  1  0.260  0.325  0.354  1.0
  Ca  Ca8  1  0.500  0.774  0.960  1.0
  Ca  Ca9  1  0.500  0.019  0.268  1.0
  Si  Si10  1  0.500  0.403  0.975  1.0
  Si  Si11  1  0.500  0.963  0.621  1.0
  Si  Si12  1  0.000  0.386  0.587  1.0
  S  S13  1  0.500  0.630  0.404  1.0
  S  S14  1  0.000  0.031  0.375  1.0
  S  S15  1  0.000  0.581  0.041  1.0
  Cl  Cl16  1  0.247  0.992  0.012  1.0
  Cl  Cl17  1  0.753  0.992  0.012  1.0
  O  O18  1  0.304  0.906  0.735  1.0
  O  O19  1  0.696  0.906  0.735  1.0
  O  O20  1  0.500  0.598  0.879  1.0
  O  O21  1  0.000  0.636  0.871  1.0
  O  O22  1  0.691  0.357  0.904  1.0
  O  O23  1  0.309  0.357  0.904  1.0
  O  O24  1  0.500  0.858  0.530  1.0
  O  O25  1  0.000  0.859  0.482  1.0
  O  O26  1  0.000  0.513  0.651  1.0
  O  O27  1  0.500  0.542  0.578  1.0
  O  O28  1  0.193  0.268  0.642  1.0
  O  O29  1  0.807  0.268  0.642  1.0
  O  O30  1  0.677  0.731  0.349  1.0
  O  O31  1  0.323  0.731  0.349  1.0
  O  O32  1  0.000  0.472  0.393  1.0
  O  O33  1  0.500  0.517  0.342  1.0
  O  O34  1  0.500  0.150  0.493  1.0
  O  O35  1  0.000  0.119  0.465  1.0
  O  O36  1  0.176  0.639  0.086  1.0
  O  O37  1  0.824  0.639  0.086  1.0
  O  O38  1  0.500  0.323  0.166  1.0
  O  O39  1  0.000  0.405  0.129  1.0
  O  O40  1  0.175  0.082  0.273  1.0
  O  O41  1  0.825  0.082  0.273  1.0
[/CIF]
.