The material described by Ca3TlO5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(3), two equivalent O(1), and three equivalent O(2) atoms to form CaO6 octahedra that share  a cornercorner with one Ca(1)O6 octahedra, corners with two equivalent Tl(1)O6 octahedra, edges with three equivalent Tl(1)O6 octahedra, and edges with four equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-65°. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. Tl(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form TlO6 octahedra that share corners with four equivalent Ca(1)O6 octahedra, edges with two equivalent Tl(1)O6 octahedra, and edges with six equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Tl(1) atom to form distorted OCa4Tl trigonal bipyramids that share corners with four equivalent O(2)Ca3Tl2 square pyramids, corners with four equivalent O(3)Ca4 tetrahedra, corners with three equivalent O(1)Ca4Tl trigonal bipyramids, edges with three equivalent O(2)Ca3Tl2 square pyramids,  an edgeedge with one O(3)Ca4 tetrahedra, and edges with three equivalent O(1)Ca4Tl trigonal bipyramids. In the second O site, O(2) is bonded to three equivalent Ca(1) and two equivalent Tl(1) atoms to form distorted OCa3Tl2 square pyramids that share corners with two equivalent O(2)Ca3Tl2 square pyramids, corners with three equivalent O(3)Ca4 tetrahedra, corners with four equivalent O(1)Ca4Tl trigonal bipyramids, edges with five equivalent O(2)Ca3Tl2 square pyramids, and edges with three equivalent O(1)Ca4Tl trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Ca(1) and two equivalent Ca(2) atoms to form OCa4 tetrahedra that share corners with six equivalent O(2)Ca3Tl2 square pyramids, corners with two equivalent O(3)Ca4 tetrahedra, corners with eight equivalent O(1)Ca4Tl trigonal bipyramids, and edges with two equivalent O(1)Ca4Tl trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca3TlO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.912
_cell_length_b   5.912
_cell_length_c   13.647
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   146.814
_symmetry_Int_Tables_number   1
_cell_volume   261.119
_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  0.729  0.271  0.113  1.0
  Ca  Ca1  1  0.271  0.729  0.887  1.0
  Ca  Ca2  1  0.271  0.729  0.613  1.0
  Ca  Ca3  1  0.729  0.271  0.387  1.0
  Ca  Ca4  1  0.472  0.528  0.250  1.0
  Ca  Ca5  1  0.528  0.472  0.750  1.0
  Tl  Tl6  1  0.000  0.000  0.000  1.0
  Tl  Tl7  1  0.000  0.000  0.500  1.0
  O  O8  1  0.916  0.084  0.645  1.0
  O  O9  1  0.084  0.916  0.355  1.0
  O  O10  1  0.084  0.916  0.145  1.0
  O  O11  1  0.916  0.084  0.855  1.0
  O  O12  1  0.639  0.361  0.548  1.0
  O  O13  1  0.361  0.639  0.452  1.0
  O  O14  1  0.361  0.639  0.048  1.0
  O  O15  1  0.639  0.361  0.952  1.0
  O  O16  1  0.834  0.166  0.250  1.0
  O  O17  1  0.166  0.834  0.750  1.0
[/CIF]
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The material described by Ca3TlO5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(3), two equivalent O(1), and three equivalent O(2) atoms to form CaO6 octahedra that share  a cornercorner with one Ca(1)O6 octahedra, corners with two equivalent Tl(1)O6 octahedra, edges with three equivalent Tl(1)O6 octahedra, and edges with four equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-65°. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(1) atoms. Tl(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form TlO6 octahedra that share corners with four equivalent Ca(1)O6 octahedra, edges with two equivalent Tl(1)O6 octahedra, and edges with six equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Tl(1) atom to form distorted OCa4Tl trigonal bipyramids that share corners with four equivalent O(2)Ca3Tl2 square pyramids, corners with four equivalent O(3)Ca4 tetrahedra, corners with three equivalent O(1)Ca4Tl trigonal bipyramids, edges with three equivalent O(2)Ca3Tl2 square pyramids,  an edgeedge with one O(3)Ca4 tetrahedra, and edges with three equivalent O(1)Ca4Tl trigonal bipyramids. In the second O site, O(2) is bonded to three equivalent Ca(1) and two equivalent Tl(1) atoms to form distorted OCa3Tl2 square pyramids that share corners with two equivalent O(2)Ca3Tl2 square pyramids, corners with three equivalent O(3)Ca4 tetrahedra, corners with four equivalent O(1)Ca4Tl trigonal bipyramids, edges with five equivalent O(2)Ca3Tl2 square pyramids, and edges with three equivalent O(1)Ca4Tl trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Ca(1) and two equivalent Ca(2) atoms to form OCa4 tetrahedra that share corners with six equivalent O(2)Ca3Tl2 square pyramids, corners with two equivalent O(3)Ca4 tetrahedra, corners with eight equivalent O(1)Ca4Tl trigonal bipyramids, and edges with two equivalent O(1)Ca4Tl trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca3TlO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.912
_cell_length_b   5.912
_cell_length_c   13.647
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   146.814
_symmetry_Int_Tables_number   1
_cell_volume   261.119
_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  0.729  0.271  0.113  1.0
  Ca  Ca1  1  0.271  0.729  0.887  1.0
  Ca  Ca2  1  0.271  0.729  0.613  1.0
  Ca  Ca3  1  0.729  0.271  0.387  1.0
  Ca  Ca4  1  0.472  0.528  0.250  1.0
  Ca  Ca5  1  0.528  0.472  0.750  1.0
  Tl  Tl6  1  0.000  0.000  0.000  1.0
  Tl  Tl7  1  0.000  0.000  0.500  1.0
  O  O8  1  0.916  0.084  0.645  1.0
  O  O9  1  0.084  0.916  0.355  1.0
  O  O10  1  0.084  0.916  0.145  1.0
  O  O11  1  0.916  0.084  0.855  1.0
  O  O12  1  0.639  0.361  0.548  1.0
  O  O13  1  0.361  0.639  0.452  1.0
  O  O14  1  0.361  0.639  0.048  1.0
  O  O15  1  0.639  0.361  0.952  1.0
  O  O16  1  0.834  0.166  0.250  1.0
  O  O17  1  0.166  0.834  0.750  1.0
[/CIF]
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