The compound described by Ca4Al6SO16 crystallizes in the tetragonal I-4 space group. Ca(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted CaO4 tetrahedra that share  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra, and corners with four equivalent Al(1)O4 tetrahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form AlO4 tetrahedra that share  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with four equivalent Ca(1)O4 tetrahedra. In the second Al site, Al(2) is bonded to four equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Ca(1)O4 tetrahedra and corners with four equivalent Al(1)O4 tetrahedra. In the third Al site, Al(3) is bonded to four equivalent O(1) atoms to form AlO4 tetrahedra that share corners with four equivalent Ca(1)O4 tetrahedra and corners with four equivalent Al(1)O4 tetrahedra. S(1) is bonded to four equivalent O(4) atoms to form SO4 tetrahedra that share corners with four equivalent Ca(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a bent 120 degrees geometry to one Ca(1) and one S(1) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Ca(1), one Al(1), and one Al(3) atom. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(1), one Al(1), and one Al(2) atom. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1) and two equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_Ca4Al6SO16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.078
_cell_length_b   8.078
_cell_length_c   8.078
_cell_angle_alpha   109.517
_cell_angle_beta   109.517
_cell_angle_gamma   109.380
_symmetry_Int_Tables_number   1
_cell_volume   405.758
_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  0.426  0.004  0.010  1.0
  Ca  Ca1  1  0.996  0.006  0.422  1.0
  Ca  Ca2  1  0.994  0.415  0.990  1.0
  Ca  Ca3  1  0.585  0.574  0.578  1.0
  Al  Al4  1  0.500  0.749  0.252  1.0
  Al  Al5  1  0.250  0.750  0.500  1.0
  Al  Al6  1  0.752  0.500  0.249  1.0
  Al  Al7  1  0.750  0.250  0.500  1.0
  Al  Al8  1  0.497  0.248  0.748  1.0
  Al  Al9  1  0.251  0.503  0.751  1.0
  S  S10  1  0.000  0.000  0.000  1.0
  O  O11  1  0.600  0.998  0.297  1.0
  O  O12  1  0.310  0.713  0.711  1.0
  O  O13  1  0.599  0.291  0.999  1.0
  O  O14  1  0.287  0.999  0.597  1.0
  O  O15  1  0.002  0.298  0.602  1.0
  O  O16  1  0.709  0.708  0.308  1.0
  O  O17  1  0.702  0.303  0.703  1.0
  O  O18  1  0.001  0.598  0.289  1.0
  O  O19  1  0.292  0.600  0.001  1.0
  O  O20  1  0.402  0.690  0.403  1.0
  O  O21  1  0.697  0.400  0.398  1.0
  O  O22  1  0.400  0.401  0.692  1.0
  O  O23  1  0.911  0.040  0.133  1.0
  O  O24  1  0.960  0.093  0.871  1.0
  O  O25  1  0.907  0.778  0.867  1.0
  O  O26  1  0.222  0.089  0.129  1.0
[/CIF]
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The compound described by Ca4Al6SO16 crystallizes in the tetragonal I-4 space group. Ca(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted CaO4 tetrahedra that share  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra,  a cornercorner with one S(1)O4 tetrahedra, and corners with four equivalent Al(1)O4 tetrahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form AlO4 tetrahedra that share  a cornercorner with one Al(2)O4 tetrahedra,  a cornercorner with one Al(3)O4 tetrahedra, corners with two equivalent Al(1)O4 tetrahedra, and corners with four equivalent Ca(1)O4 tetrahedra. In the second Al site, Al(2) is bonded to four equivalent O(2) atoms to form AlO4 tetrahedra that share corners with four equivalent Ca(1)O4 tetrahedra and corners with four equivalent Al(1)O4 tetrahedra. In the third Al site, Al(3) is bonded to four equivalent O(1) atoms to form AlO4 tetrahedra that share corners with four equivalent Ca(1)O4 tetrahedra and corners with four equivalent Al(1)O4 tetrahedra. S(1) is bonded to four equivalent O(4) atoms to form SO4 tetrahedra that share corners with four equivalent Ca(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a bent 120 degrees geometry to one Ca(1) and one S(1) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Ca(1), one Al(1), and one Al(3) atom. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(1), one Al(1), and one Al(2) atom. In the fourth O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1) and two equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_Ca4Al6SO16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.078
_cell_length_b   8.078
_cell_length_c   8.078
_cell_angle_alpha   109.517
_cell_angle_beta   109.517
_cell_angle_gamma   109.380
_symmetry_Int_Tables_number   1
_cell_volume   405.758
_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  0.426  0.004  0.010  1.0
  Ca  Ca1  1  0.996  0.006  0.422  1.0
  Ca  Ca2  1  0.994  0.415  0.990  1.0
  Ca  Ca3  1  0.585  0.574  0.578  1.0
  Al  Al4  1  0.500  0.749  0.252  1.0
  Al  Al5  1  0.250  0.750  0.500  1.0
  Al  Al6  1  0.752  0.500  0.249  1.0
  Al  Al7  1  0.750  0.250  0.500  1.0
  Al  Al8  1  0.497  0.248  0.748  1.0
  Al  Al9  1  0.251  0.503  0.751  1.0
  S  S10  1  0.000  0.000  0.000  1.0
  O  O11  1  0.600  0.998  0.297  1.0
  O  O12  1  0.310  0.713  0.711  1.0
  O  O13  1  0.599  0.291  0.999  1.0
  O  O14  1  0.287  0.999  0.597  1.0
  O  O15  1  0.002  0.298  0.602  1.0
  O  O16  1  0.709  0.708  0.308  1.0
  O  O17  1  0.702  0.303  0.703  1.0
  O  O18  1  0.001  0.598  0.289  1.0
  O  O19  1  0.292  0.600  0.001  1.0
  O  O20  1  0.402  0.690  0.403  1.0
  O  O21  1  0.697  0.400  0.398  1.0
  O  O22  1  0.400  0.401  0.692  1.0
  O  O23  1  0.911  0.040  0.133  1.0
  O  O24  1  0.960  0.093  0.871  1.0
  O  O25  1  0.907  0.778  0.867  1.0
  O  O26  1  0.222  0.089  0.129  1.0
[/CIF]
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