The material structure described by Ca3UO6 is Ilmenite-like structured and crystallizes in the trigonal R-3 space group. Ca(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted CaO6 pentagonal pyramids that share  a cornercorner with one U(1)O6 octahedra,  a cornercorner with one U(2)O6 octahedra, corners with four equivalent Ca(1)O6 pentagonal pyramids,  an edgeedge with one U(1)O6 octahedra,  an edgeedge with one U(2)O6 octahedra, and edges with four equivalent Ca(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 36-43°. There are two inequivalent U sites. In the first U site, U(1) is bonded to six equivalent O(1) atoms to form UO6 octahedra that share corners with six equivalent Ca(1)O6 pentagonal pyramids and edges with six equivalent Ca(1)O6 pentagonal pyramids. In the second U site, U(2) is bonded to six equivalent O(2) atoms to form UO6 octahedra that share corners with six equivalent Ca(1)O6 pentagonal pyramids and edges with six equivalent Ca(1)O6 pentagonal pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ca(1) and one U(1) atom to form a mixture of distorted corner and edge-sharing OCa3U trigonal pyramids. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to three equivalent Ca(1) and one U(2) atom. is represented by the CIF card [CIF]
data_Ca3UO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.740
_cell_length_b   6.740
_cell_length_c   6.740
_cell_angle_alpha   91.343
_cell_angle_beta   91.343
_cell_angle_gamma   91.343
_symmetry_Int_Tables_number   1
_cell_volume   305.917
_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  0.061  0.557  0.251  1.0
  Ca  Ca1  1  0.251  0.061  0.557  1.0
  Ca  Ca2  1  0.443  0.749  0.939  1.0
  Ca  Ca3  1  0.749  0.939  0.443  1.0
  Ca  Ca4  1  0.939  0.443  0.749  1.0
  Ca  Ca5  1  0.557  0.251  0.061  1.0
  U  U6  1  0.000  0.000  0.000  1.0
  U  U7  1  0.500  0.500  0.500  1.0
  O  O8  1  0.707  0.935  0.075  1.0
  O  O9  1  0.935  0.075  0.707  1.0
  O  O10  1  0.075  0.707  0.935  1.0
  O  O11  1  0.293  0.065  0.925  1.0
  O  O12  1  0.065  0.925  0.293  1.0
  O  O13  1  0.925  0.293  0.065  1.0
  O  O14  1  0.794  0.587  0.459  1.0
  O  O15  1  0.587  0.459  0.794  1.0
  O  O16  1  0.541  0.206  0.413  1.0
  O  O17  1  0.413  0.541  0.206  1.0
  O  O18  1  0.206  0.413  0.541  1.0
  O  O19  1  0.459  0.794  0.587  1.0
[/CIF]
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The material structure described by Ca3UO6 is Ilmenite-like structured and crystallizes in the trigonal R-3 space group. Ca(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted CaO6 pentagonal pyramids that share  a cornercorner with one U(1)O6 octahedra,  a cornercorner with one U(2)O6 octahedra, corners with four equivalent Ca(1)O6 pentagonal pyramids,  an edgeedge with one U(1)O6 octahedra,  an edgeedge with one U(2)O6 octahedra, and edges with four equivalent Ca(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 36-43°. There are two inequivalent U sites. In the first U site, U(1) is bonded to six equivalent O(1) atoms to form UO6 octahedra that share corners with six equivalent Ca(1)O6 pentagonal pyramids and edges with six equivalent Ca(1)O6 pentagonal pyramids. In the second U site, U(2) is bonded to six equivalent O(2) atoms to form UO6 octahedra that share corners with six equivalent Ca(1)O6 pentagonal pyramids and edges with six equivalent Ca(1)O6 pentagonal pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ca(1) and one U(1) atom to form a mixture of distorted corner and edge-sharing OCa3U trigonal pyramids. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to three equivalent Ca(1) and one U(2) atom. is represented by the CIF card [CIF]
data_Ca3UO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.740
_cell_length_b   6.740
_cell_length_c   6.740
_cell_angle_alpha   91.343
_cell_angle_beta   91.343
_cell_angle_gamma   91.343
_symmetry_Int_Tables_number   1
_cell_volume   305.917
_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  0.061  0.557  0.251  1.0
  Ca  Ca1  1  0.251  0.061  0.557  1.0
  Ca  Ca2  1  0.443  0.749  0.939  1.0
  Ca  Ca3  1  0.749  0.939  0.443  1.0
  Ca  Ca4  1  0.939  0.443  0.749  1.0
  Ca  Ca5  1  0.557  0.251  0.061  1.0
  U  U6  1  0.000  0.000  0.000  1.0
  U  U7  1  0.500  0.500  0.500  1.0
  O  O8  1  0.707  0.935  0.075  1.0
  O  O9  1  0.935  0.075  0.707  1.0
  O  O10  1  0.075  0.707  0.935  1.0
  O  O11  1  0.293  0.065  0.925  1.0
  O  O12  1  0.065  0.925  0.293  1.0
  O  O13  1  0.925  0.293  0.065  1.0
  O  O14  1  0.794  0.587  0.459  1.0
  O  O15  1  0.587  0.459  0.794  1.0
  O  O16  1  0.541  0.206  0.413  1.0
  O  O17  1  0.413  0.541  0.206  1.0
  O  O18  1  0.206  0.413  0.541  1.0
  O  O19  1  0.459  0.794  0.587  1.0
[/CIF]
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