The structure described by Ca2Mo3O8 is beta indium sulfide-derived structured and crystallizes in the monoclinic C2/m space group. Ca(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted CaO6 pentagonal pyramids that share corners with three equivalent Mo(1)O6 octahedra, corners with four equivalent Mo(2)O6 octahedra,  an edgeedge with one Mo(1)O6 octahedra, edges with two equivalent Mo(2)O6 octahedra, and edges with two equivalent Ca(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 5-53°. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MoO6 octahedra that share corners with six equivalent Ca(1)O6 pentagonal pyramids, edges with four equivalent Mo(2)O6 octahedra, and edges with two equivalent Ca(1)O6 pentagonal pyramids. In the second Mo site, Mo(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MoO6 octahedra that share corners with four equivalent Ca(1)O6 pentagonal pyramids, edges with two equivalent Mo(1)O6 octahedra, edges with two equivalent Mo(2)O6 octahedra, and edges with two equivalent Ca(1)O6 pentagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ca(1) and two equivalent Mo(2) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Mo(1), and two equivalent Mo(2) atoms. In the third O site, O(3) is bonded to two equivalent Ca(1), one Mo(1), and one Mo(2) atom to form a mixture of distorted corner and edge-sharing OCa2Mo2 trigonal pyramids. is represented by the CIF card [CIF]
data_Ca2Mo3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.499
_cell_length_b   6.499
_cell_length_c   4.918
_cell_angle_alpha   76.541
_cell_angle_beta   76.541
_cell_angle_gamma   52.982
_symmetry_Int_Tables_number   1
_cell_volume   160.142
_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  0.727  0.727  0.327  1.0
  Ca  Ca1  1  0.273  0.273  0.673  1.0
  Mo  Mo2  1  0.000  0.000  0.500  1.0
  Mo  Mo3  1  0.771  0.229  0.000  1.0
  Mo  Mo4  1  0.229  0.771  0.000  1.0
  O  O5  1  0.410  0.410  0.913  1.0
  O  O6  1  0.590  0.590  0.087  1.0
  O  O7  1  0.877  0.877  0.903  1.0
  O  O8  1  0.123  0.123  0.097  1.0
  O  O9  1  0.342  0.876  0.608  1.0
  O  O10  1  0.876  0.342  0.608  1.0
  O  O11  1  0.124  0.658  0.392  1.0
  O  O12  1  0.658  0.124  0.392  1.0
[/CIF]
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The structure described by Ca2Mo3O8 is beta indium sulfide-derived structured and crystallizes in the monoclinic C2/m space group. Ca(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted CaO6 pentagonal pyramids that share corners with three equivalent Mo(1)O6 octahedra, corners with four equivalent Mo(2)O6 octahedra,  an edgeedge with one Mo(1)O6 octahedra, edges with two equivalent Mo(2)O6 octahedra, and edges with two equivalent Ca(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 5-53°. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MoO6 octahedra that share corners with six equivalent Ca(1)O6 pentagonal pyramids, edges with four equivalent Mo(2)O6 octahedra, and edges with two equivalent Ca(1)O6 pentagonal pyramids. In the second Mo site, Mo(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MoO6 octahedra that share corners with four equivalent Ca(1)O6 pentagonal pyramids, edges with two equivalent Mo(1)O6 octahedra, edges with two equivalent Mo(2)O6 octahedra, and edges with two equivalent Ca(1)O6 pentagonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ca(1) and two equivalent Mo(2) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Mo(1), and two equivalent Mo(2) atoms. In the third O site, O(3) is bonded to two equivalent Ca(1), one Mo(1), and one Mo(2) atom to form a mixture of distorted corner and edge-sharing OCa2Mo2 trigonal pyramids. is represented by the CIF card [CIF]
data_Ca2Mo3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.499
_cell_length_b   6.499
_cell_length_c   4.918
_cell_angle_alpha   76.541
_cell_angle_beta   76.541
_cell_angle_gamma   52.982
_symmetry_Int_Tables_number   1
_cell_volume   160.142
_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  0.727  0.727  0.327  1.0
  Ca  Ca1  1  0.273  0.273  0.673  1.0
  Mo  Mo2  1  0.000  0.000  0.500  1.0
  Mo  Mo3  1  0.771  0.229  0.000  1.0
  Mo  Mo4  1  0.229  0.771  0.000  1.0
  O  O5  1  0.410  0.410  0.913  1.0
  O  O6  1  0.590  0.590  0.087  1.0
  O  O7  1  0.877  0.877  0.903  1.0
  O  O8  1  0.123  0.123  0.097  1.0
  O  O9  1  0.342  0.876  0.608  1.0
  O  O10  1  0.876  0.342  0.608  1.0
  O  O11  1  0.124  0.658  0.392  1.0
  O  O12  1  0.658  0.124  0.392  1.0
[/CIF]
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