The compound described by CsCa(SeO4)3 crystallizes in the monoclinic P2_1/m space group. Cs(1) is bonded in a 13-coordinate geometry to one O(5), one O(7), one O(8), two equivalent O(1), two equivalent O(3), two equivalent O(4), two equivalent O(6), and two equivalent O(9) atoms. Ca(1) is bonded to one O(2), one O(5), one O(8), two equivalent O(3), and two equivalent O(9) atoms to form distorted CaO7 pentagonal bipyramids that share  a cornercorner with one Se(2)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra, and corners with three equivalent Se(3)O4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SeO4 tetrahedra that share corners with three equivalent Ca(1)O7 pentagonal bipyramids. In the second Se site, Se(2) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form SeO4 tetrahedra that share  a cornercorner with one Ca(1)O7 pentagonal bipyramid. In the third Se site, Se(3) is bonded to one O(7), one O(8), and two equivalent O(9) atoms to form SeO4 tetrahedra that share corners with three equivalent Ca(1)O7 pentagonal bipyramids. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to two equivalent Cs(1) and one Se(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ca(1) and one Se(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Cs(1), one Ca(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to two equivalent Cs(1) and one Se(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cs(1), one Ca(1), and one Se(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Cs(1) and one Se(2) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Cs(1) and one Se(3) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Cs(1), one Ca(1), and one Se(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Cs(1), one Ca(1), and one Se(3) atom. is represented by the CIF file [CIF]
data_CsCa(SeO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.064
_cell_length_b   8.756
_cell_length_c   11.961
_cell_angle_alpha   73.351
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   608.430
_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
  Cs  Cs0  1  0.250  0.134  0.727  1.0
  Cs  Cs1  1  0.750  0.866  0.273  1.0
  Ca  Ca2  1  0.250  0.615  0.852  1.0
  Ca  Ca3  1  0.750  0.385  0.148  1.0
  Se  Se4  1  0.750  0.425  0.801  1.0
  Se  Se5  1  0.250  0.575  0.199  1.0
  Se  Se6  1  0.250  0.780  0.531  1.0
  Se  Se7  1  0.750  0.220  0.469  1.0
  Se  Se8  1  0.250  0.190  0.058  1.0
  Se  Se9  1  0.750  0.810  0.942  1.0
  O  O10  1  0.750  0.232  0.803  1.0
  O  O11  1  0.250  0.768  0.197  1.0
  O  O12  1  0.250  0.547  0.066  1.0
  O  O13  1  0.750  0.453  0.934  1.0
  O  O14  1  0.981  0.511  0.733  1.0
  O  O15  1  0.481  0.489  0.267  1.0
  O  O16  1  0.019  0.489  0.267  1.0
  O  O17  1  0.519  0.511  0.733  1.0
  O  O18  1  0.750  0.052  0.581  1.0
  O  O19  1  0.250  0.948  0.419  1.0
  O  O20  1  0.250  0.815  0.660  1.0
  O  O21  1  0.750  0.185  0.340  1.0
  O  O22  1  0.979  0.318  0.490  1.0
  O  O23  1  0.479  0.682  0.510  1.0
  O  O24  1  0.021  0.682  0.510  1.0
  O  O25  1  0.521  0.318  0.490  1.0
  O  O26  1  0.250  0.016  0.019  1.0
  O  O27  1  0.750  0.984  0.981  1.0
  O  O28  1  0.250  0.324  0.926  1.0
  O  O29  1  0.750  0.676  0.074  1.0
  O  O30  1  0.023  0.199  0.133  1.0
  O  O31  1  0.523  0.801  0.867  1.0
  O  O32  1  0.977  0.801  0.867  1.0
  O  O33  1  0.477  0.199  0.133  1.0
[/CIF]
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The compound described by CsCa(SeO4)3 crystallizes in the monoclinic P2_1/m space group. Cs(1) is bonded in a 13-coordinate geometry to one O(5), one O(7), one O(8), two equivalent O(1), two equivalent O(3), two equivalent O(4), two equivalent O(6), and two equivalent O(9) atoms. Ca(1) is bonded to one O(2), one O(5), one O(8), two equivalent O(3), and two equivalent O(9) atoms to form distorted CaO7 pentagonal bipyramids that share  a cornercorner with one Se(2)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra, and corners with three equivalent Se(3)O4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form SeO4 tetrahedra that share corners with three equivalent Ca(1)O7 pentagonal bipyramids. In the second Se site, Se(2) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form SeO4 tetrahedra that share  a cornercorner with one Ca(1)O7 pentagonal bipyramid. In the third Se site, Se(3) is bonded to one O(7), one O(8), and two equivalent O(9) atoms to form SeO4 tetrahedra that share corners with three equivalent Ca(1)O7 pentagonal bipyramids. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to two equivalent Cs(1) and one Se(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ca(1) and one Se(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Cs(1), one Ca(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to two equivalent Cs(1) and one Se(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cs(1), one Ca(1), and one Se(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Cs(1) and one Se(2) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Cs(1) and one Se(3) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Cs(1), one Ca(1), and one Se(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Cs(1), one Ca(1), and one Se(3) atom. is represented by the CIF file [CIF]
data_CsCa(SeO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.064
_cell_length_b   8.756
_cell_length_c   11.961
_cell_angle_alpha   73.351
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   608.430
_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
  Cs  Cs0  1  0.250  0.134  0.727  1.0
  Cs  Cs1  1  0.750  0.866  0.273  1.0
  Ca  Ca2  1  0.250  0.615  0.852  1.0
  Ca  Ca3  1  0.750  0.385  0.148  1.0
  Se  Se4  1  0.750  0.425  0.801  1.0
  Se  Se5  1  0.250  0.575  0.199  1.0
  Se  Se6  1  0.250  0.780  0.531  1.0
  Se  Se7  1  0.750  0.220  0.469  1.0
  Se  Se8  1  0.250  0.190  0.058  1.0
  Se  Se9  1  0.750  0.810  0.942  1.0
  O  O10  1  0.750  0.232  0.803  1.0
  O  O11  1  0.250  0.768  0.197  1.0
  O  O12  1  0.250  0.547  0.066  1.0
  O  O13  1  0.750  0.453  0.934  1.0
  O  O14  1  0.981  0.511  0.733  1.0
  O  O15  1  0.481  0.489  0.267  1.0
  O  O16  1  0.019  0.489  0.267  1.0
  O  O17  1  0.519  0.511  0.733  1.0
  O  O18  1  0.750  0.052  0.581  1.0
  O  O19  1  0.250  0.948  0.419  1.0
  O  O20  1  0.250  0.815  0.660  1.0
  O  O21  1  0.750  0.185  0.340  1.0
  O  O22  1  0.979  0.318  0.490  1.0
  O  O23  1  0.479  0.682  0.510  1.0
  O  O24  1  0.021  0.682  0.510  1.0
  O  O25  1  0.521  0.318  0.490  1.0
  O  O26  1  0.250  0.016  0.019  1.0
  O  O27  1  0.750  0.984  0.981  1.0
  O  O28  1  0.250  0.324  0.926  1.0
  O  O29  1  0.750  0.676  0.074  1.0
  O  O30  1  0.023  0.199  0.133  1.0
  O  O31  1  0.523  0.801  0.867  1.0
  O  O32  1  0.977  0.801  0.867  1.0
  O  O33  1  0.477  0.199  0.133  1.0
[/CIF]
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