The crystal structure described by Ba2CaCu(HgO3)2 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. Ca(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. Cu(1) is bonded in a linear geometry to two equivalent O(2) atoms. Hg(1) is bonded to one O(2) and four equivalent O(1) atoms to form corner-sharing HgO5 square pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Ca(1), and two equivalent Hg(1) atoms to form a mixture of distorted edge, corner, and face-sharing OBa2Ca2Hg2 octahedra. The corner-sharing octahedral tilt angles range from 0-70°. In the second O site, O(2) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Cu(1), and one Hg(1) atom. is represented by the CIF file [CIF]
data_Ba2CaCu(HgO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.272
_cell_length_b   4.272
_cell_length_c   12.085
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   220.542
_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
  Ba  Ba0  1  0.500  0.500  0.197  1.0
  Ba  Ba1  1  0.500  0.500  0.803  1.0
  Ca  Ca2  1  0.500  0.500  0.500  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Hg  Hg4  1  0.000  0.000  0.361  1.0
  Hg  Hg5  1  0.000  0.000  0.639  1.0
  O  O6  1  0.000  0.500  0.372  1.0
  O  O7  1  0.000  0.500  0.628  1.0
  O  O8  1  0.500  0.000  0.372  1.0
  O  O9  1  0.500  0.000  0.628  1.0
  O  O10  1  0.000  0.000  0.149  1.0
  O  O11  1  0.000  0.000  0.851  1.0
[/CIF]
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The crystal structure described by Ba2CaCu(HgO3)2 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. Ca(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. Cu(1) is bonded in a linear geometry to two equivalent O(2) atoms. Hg(1) is bonded to one O(2) and four equivalent O(1) atoms to form corner-sharing HgO5 square pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Ca(1), and two equivalent Hg(1) atoms to form a mixture of distorted edge, corner, and face-sharing OBa2Ca2Hg2 octahedra. The corner-sharing octahedral tilt angles range from 0-70°. In the second O site, O(2) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Cu(1), and one Hg(1) atom. is represented by the CIF file [CIF]
data_Ba2CaCu(HgO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.272
_cell_length_b   4.272
_cell_length_c   12.085
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   220.542
_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
  Ba  Ba0  1  0.500  0.500  0.197  1.0
  Ba  Ba1  1  0.500  0.500  0.803  1.0
  Ca  Ca2  1  0.500  0.500  0.500  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Hg  Hg4  1  0.000  0.000  0.361  1.0
  Hg  Hg5  1  0.000  0.000  0.639  1.0
  O  O6  1  0.000  0.500  0.372  1.0
  O  O7  1  0.000  0.500  0.628  1.0
  O  O8  1  0.500  0.000  0.372  1.0
  O  O9  1  0.500  0.000  0.628  1.0
  O  O10  1  0.000  0.000  0.149  1.0
  O  O11  1  0.000  0.000  0.851  1.0
[/CIF]
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