The material described by Ca2Ta2SnO8 crystallizes in the monoclinic C2/c space group. Ca(1) is bonded in a 6-coordinate geometry to three equivalent O(3) and three equivalent O(4) atoms. Ta(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted edge-sharing TaO6 octahedra. Sn(1) is bonded in a see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Ta(1) and one Sn(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ta(1) and one Sn(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to three equivalent Ca(1) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded to three equivalent Ca(1) and one Ta(1) atom to form a mixture of distorted edge and corner-sharing OCa3Ta trigonal pyramids. is represented by the CIF card [CIF]
data_Ca2Ta2SnO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.715
_cell_length_b   10.715
_cell_length_c   5.502
_cell_angle_alpha   89.798
_cell_angle_beta   89.798
_cell_angle_gamma   36.847
_symmetry_Int_Tables_number   1
_cell_volume   378.768
_cell_formula_units_Z   2
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  0.569  0.863  0.250  1.0
  Ca  Ca1  1  0.137  0.431  0.250  1.0
  Ca  Ca2  1  0.431  0.137  0.750  1.0
  Ca  Ca3  1  0.863  0.569  0.750  1.0
  Ta  Ta4  1  0.734  0.020  0.254  1.0
  Ta  Ta5  1  0.980  0.266  0.246  1.0
  Ta  Ta6  1  0.266  0.980  0.746  1.0
  Ta  Ta7  1  0.020  0.734  0.754  1.0
  Sn  Sn8  1  0.314  0.686  0.250  1.0
  Sn  Sn9  1  0.686  0.314  0.750  1.0
  O  O10  1  0.825  0.018  0.932  1.0
  O  O11  1  0.982  0.175  0.568  1.0
  O  O12  1  0.175  0.982  0.068  1.0
  O  O13  1  0.018  0.825  0.432  1.0
  O  O14  1  0.602  0.259  0.393  1.0
  O  O15  1  0.741  0.398  0.107  1.0
  O  O16  1  0.398  0.741  0.607  1.0
  O  O17  1  0.259  0.602  0.893  1.0
  O  O18  1  0.735  0.891  0.527  1.0
  O  O19  1  0.109  0.265  0.973  1.0
  O  O20  1  0.142  0.478  0.645  1.0
  O  O21  1  0.522  0.858  0.855  1.0
  O  O22  1  0.858  0.522  0.355  1.0
  O  O23  1  0.478  0.142  0.145  1.0
  O  O24  1  0.891  0.735  0.027  1.0
  O  O25  1  0.265  0.109  0.473  1.0
[/CIF]
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The material described by Ca2Ta2SnO8 crystallizes in the monoclinic C2/c space group. Ca(1) is bonded in a 6-coordinate geometry to three equivalent O(3) and three equivalent O(4) atoms. Ta(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted edge-sharing TaO6 octahedra. Sn(1) is bonded in a see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Ta(1) and one Sn(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ta(1) and one Sn(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to three equivalent Ca(1) and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded to three equivalent Ca(1) and one Ta(1) atom to form a mixture of distorted edge and corner-sharing OCa3Ta trigonal pyramids. is represented by the CIF card [CIF]
data_Ca2Ta2SnO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.715
_cell_length_b   10.715
_cell_length_c   5.502
_cell_angle_alpha   89.798
_cell_angle_beta   89.798
_cell_angle_gamma   36.847
_symmetry_Int_Tables_number   1
_cell_volume   378.768
_cell_formula_units_Z   2
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  0.569  0.863  0.250  1.0
  Ca  Ca1  1  0.137  0.431  0.250  1.0
  Ca  Ca2  1  0.431  0.137  0.750  1.0
  Ca  Ca3  1  0.863  0.569  0.750  1.0
  Ta  Ta4  1  0.734  0.020  0.254  1.0
  Ta  Ta5  1  0.980  0.266  0.246  1.0
  Ta  Ta6  1  0.266  0.980  0.746  1.0
  Ta  Ta7  1  0.020  0.734  0.754  1.0
  Sn  Sn8  1  0.314  0.686  0.250  1.0
  Sn  Sn9  1  0.686  0.314  0.750  1.0
  O  O10  1  0.825  0.018  0.932  1.0
  O  O11  1  0.982  0.175  0.568  1.0
  O  O12  1  0.175  0.982  0.068  1.0
  O  O13  1  0.018  0.825  0.432  1.0
  O  O14  1  0.602  0.259  0.393  1.0
  O  O15  1  0.741  0.398  0.107  1.0
  O  O16  1  0.398  0.741  0.607  1.0
  O  O17  1  0.259  0.602  0.893  1.0
  O  O18  1  0.735  0.891  0.527  1.0
  O  O19  1  0.109  0.265  0.973  1.0
  O  O20  1  0.142  0.478  0.645  1.0
  O  O21  1  0.522  0.858  0.855  1.0
  O  O22  1  0.858  0.522  0.355  1.0
  O  O23  1  0.478  0.142  0.145  1.0
  O  O24  1  0.891  0.735  0.027  1.0
  O  O25  1  0.265  0.109  0.473  1.0
[/CIF]
.