The compound described by CaBi2O4 crystallizes in the orthorhombic Pbcm space group. Ca(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. Bi(1) is bonded to one O(3), two equivalent O(2), and three equivalent O(1) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 6-64°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1) and three equivalent Bi(1) atoms to form distorted OCa2Bi3 trigonal bipyramids that share corners with five equivalent O(3)Ca2Bi2 tetrahedra, corners with two equivalent O(1)Ca2Bi3 trigonal bipyramids,  an edgeedge with one O(3)Ca2Bi2 tetrahedra, and edges with five equivalent O(1)Ca2Bi3 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Bi(1) atoms. In the third O site, O(3) is bonded to two equivalent Ca(1) and two equivalent Bi(1) atoms to form OCa2Bi2 tetrahedra that share corners with two equivalent O(3)Ca2Bi2 tetrahedra, corners with ten equivalent O(1)Ca2Bi3 trigonal bipyramids, and edges with two equivalent O(1)Ca2Bi3 trigonal bipyramids. is represented by the CIF file [CIF]
data_Ca(BiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.437
_cell_length_b   11.384
_cell_length_c   11.483
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   449.335
_cell_formula_units_Z   4
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  0.809  0.750  0.365  1.0
  Ca  Ca1  1  0.809  0.250  0.135  1.0
  Ca  Ca2  1  0.191  0.750  0.865  1.0
  Ca  Ca3  1  0.191  0.250  0.635  1.0
  Bi  Bi4  1  0.288  0.577  0.119  1.0
  Bi  Bi5  1  0.288  0.077  0.381  1.0
  Bi  Bi6  1  0.712  0.077  0.881  1.0
  Bi  Bi7  1  0.288  0.423  0.381  1.0
  Bi  Bi8  1  0.712  0.423  0.881  1.0
  Bi  Bi9  1  0.288  0.923  0.119  1.0
  Bi  Bi10  1  0.712  0.923  0.619  1.0
  Bi  Bi11  1  0.712  0.577  0.619  1.0
  O  O12  1  0.725  0.879  0.976  1.0
  O  O13  1  0.275  0.121  0.024  1.0
  O  O14  1  0.738  0.000  0.250  1.0
  O  O15  1  0.275  0.879  0.476  1.0
  O  O16  1  0.275  0.621  0.476  1.0
  O  O17  1  0.311  0.250  0.275  1.0
  O  O18  1  0.725  0.121  0.524  1.0
  O  O19  1  0.689  0.250  0.775  1.0
  O  O20  1  0.738  0.500  0.250  1.0
  O  O21  1  0.262  0.000  0.750  1.0
  O  O22  1  0.725  0.621  0.976  1.0
  O  O23  1  0.689  0.750  0.725  1.0
  O  O24  1  0.311  0.750  0.225  1.0
  O  O25  1  0.262  0.500  0.750  1.0
  O  O26  1  0.725  0.379  0.524  1.0
  O  O27  1  0.275  0.379  0.024  1.0
[/CIF]
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The compound described by CaBi2O4 crystallizes in the orthorhombic Pbcm space group. Ca(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. Bi(1) is bonded to one O(3), two equivalent O(2), and three equivalent O(1) atoms to form a mixture of corner and edge-sharing BiO6 octahedra. The corner-sharing octahedral tilt angles range from 6-64°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1) and three equivalent Bi(1) atoms to form distorted OCa2Bi3 trigonal bipyramids that share corners with five equivalent O(3)Ca2Bi2 tetrahedra, corners with two equivalent O(1)Ca2Bi3 trigonal bipyramids,  an edgeedge with one O(3)Ca2Bi2 tetrahedra, and edges with five equivalent O(1)Ca2Bi3 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Bi(1) atoms. In the third O site, O(3) is bonded to two equivalent Ca(1) and two equivalent Bi(1) atoms to form OCa2Bi2 tetrahedra that share corners with two equivalent O(3)Ca2Bi2 tetrahedra, corners with ten equivalent O(1)Ca2Bi3 trigonal bipyramids, and edges with two equivalent O(1)Ca2Bi3 trigonal bipyramids. is represented by the CIF file [CIF]
data_Ca(BiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.437
_cell_length_b   11.384
_cell_length_c   11.483
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   449.335
_cell_formula_units_Z   4
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  0.809  0.750  0.365  1.0
  Ca  Ca1  1  0.809  0.250  0.135  1.0
  Ca  Ca2  1  0.191  0.750  0.865  1.0
  Ca  Ca3  1  0.191  0.250  0.635  1.0
  Bi  Bi4  1  0.288  0.577  0.119  1.0
  Bi  Bi5  1  0.288  0.077  0.381  1.0
  Bi  Bi6  1  0.712  0.077  0.881  1.0
  Bi  Bi7  1  0.288  0.423  0.381  1.0
  Bi  Bi8  1  0.712  0.423  0.881  1.0
  Bi  Bi9  1  0.288  0.923  0.119  1.0
  Bi  Bi10  1  0.712  0.923  0.619  1.0
  Bi  Bi11  1  0.712  0.577  0.619  1.0
  O  O12  1  0.725  0.879  0.976  1.0
  O  O13  1  0.275  0.121  0.024  1.0
  O  O14  1  0.738  0.000  0.250  1.0
  O  O15  1  0.275  0.879  0.476  1.0
  O  O16  1  0.275  0.621  0.476  1.0
  O  O17  1  0.311  0.250  0.275  1.0
  O  O18  1  0.725  0.121  0.524  1.0
  O  O19  1  0.689  0.250  0.775  1.0
  O  O20  1  0.738  0.500  0.250  1.0
  O  O21  1  0.262  0.000  0.750  1.0
  O  O22  1  0.725  0.621  0.976  1.0
  O  O23  1  0.689  0.750  0.725  1.0
  O  O24  1  0.311  0.750  0.225  1.0
  O  O25  1  0.262  0.500  0.750  1.0
  O  O26  1  0.725  0.379  0.524  1.0
  O  O27  1  0.275  0.379  0.024  1.0
[/CIF]
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