The structure described by Ca4Tl2CO3O6 crystallizes in the orthorhombic Imm2 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), two equivalent O(2), and two equivalent O(4) atoms to form CaO7 pentagonal bipyramids that share corners with four equivalent Ca(1)O7 pentagonal bipyramids, edges with four equivalent Tl(1)O6 octahedra, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(3), one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. Tl(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form TlO6 octahedra that share corners with four equivalent Tl(1)O6 octahedra, edges with four equivalent Tl(1)O6 octahedra, and edges with four equivalent Ca(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 3°. C(1) is bonded in a trigonal planar geometry to one O(5) and two equivalent O(4) atoms. There are five 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 OCa4Tl square pyramids that share corners with four equivalent O(1)Ca4Tl square pyramids,  a cornercorner with one O(2)Ca4Tl trigonal bipyramid, edges with four equivalent O(3)Ca2Tl4 octahedra, and edges with four equivalent O(2)Ca4Tl trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Tl(1) atom to form distorted OCa4Tl trigonal bipyramids that share  a cornercorner with one O(1)Ca4Tl square pyramid, corners with four equivalent O(2)Ca4Tl trigonal bipyramids, edges with four equivalent O(3)Ca2Tl4 octahedra, and edges with four equivalent O(1)Ca4Tl square pyramids. In the third O site, O(3) is bonded to one Ca(1), one Ca(2), and four equivalent Tl(1) atoms to form OCa2Tl4 octahedra that share corners with four equivalent O(3)Ca2Tl4 octahedra, edges with four equivalent O(3)Ca2Tl4 octahedra, edges with four equivalent O(1)Ca4Tl square pyramids, and edges with four equivalent O(2)Ca4Tl trigonal bipyramids. The corner-sharing octahedral tilt angles are 3°. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent Ca(1), two equivalent Ca(2), and one C(1) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Ca(2) and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca4Tl2CO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.870
_cell_length_b   9.870
_cell_length_c   9.870
_cell_angle_alpha   151.668
_cell_angle_beta   151.210
_cell_angle_gamma   40.834
_symmetry_Int_Tables_number   1
_cell_volume   219.271
_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  0.608  0.102  0.494  1.0
  Ca  Ca1  1  0.111  0.588  0.477  1.0
  Ca  Ca2  1  0.392  0.886  0.494  1.0
  Ca  Ca3  1  0.889  0.366  0.477  1.0
  Tl  Tl4  1  0.254  0.245  0.992  1.0
  Tl  Tl5  1  0.746  0.738  0.992  1.0
  C  C6  1  0.000  0.974  0.974  1.0
  O  O7  1  0.629  0.621  0.992  1.0
  O  O8  1  0.371  0.363  0.992  1.0
  O  O9  1  0.138  0.124  0.986  1.0
  O  O10  1  0.862  0.848  0.986  1.0
  O  O11  1  0.750  0.241  0.491  1.0
  O  O12  1  0.250  0.741  0.491  1.0
  O  O13  1  0.772  0.109  0.881  1.0
  O  O14  1  0.228  0.109  0.337  1.0
  O  O15  1  0.000  0.705  0.705  1.0
[/CIF]
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The structure described by Ca4Tl2CO3O6 crystallizes in the orthorhombic Imm2 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), two equivalent O(2), and two equivalent O(4) atoms to form CaO7 pentagonal bipyramids that share corners with four equivalent Ca(1)O7 pentagonal bipyramids, edges with four equivalent Tl(1)O6 octahedra, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(3), one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. Tl(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form TlO6 octahedra that share corners with four equivalent Tl(1)O6 octahedra, edges with four equivalent Tl(1)O6 octahedra, and edges with four equivalent Ca(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 3°. C(1) is bonded in a trigonal planar geometry to one O(5) and two equivalent O(4) atoms. There are five 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 OCa4Tl square pyramids that share corners with four equivalent O(1)Ca4Tl square pyramids,  a cornercorner with one O(2)Ca4Tl trigonal bipyramid, edges with four equivalent O(3)Ca2Tl4 octahedra, and edges with four equivalent O(2)Ca4Tl trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Ca(1), two equivalent Ca(2), and one Tl(1) atom to form distorted OCa4Tl trigonal bipyramids that share  a cornercorner with one O(1)Ca4Tl square pyramid, corners with four equivalent O(2)Ca4Tl trigonal bipyramids, edges with four equivalent O(3)Ca2Tl4 octahedra, and edges with four equivalent O(1)Ca4Tl square pyramids. In the third O site, O(3) is bonded to one Ca(1), one Ca(2), and four equivalent Tl(1) atoms to form OCa2Tl4 octahedra that share corners with four equivalent O(3)Ca2Tl4 octahedra, edges with four equivalent O(3)Ca2Tl4 octahedra, edges with four equivalent O(1)Ca4Tl square pyramids, and edges with four equivalent O(2)Ca4Tl trigonal bipyramids. The corner-sharing octahedral tilt angles are 3°. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent Ca(1), two equivalent Ca(2), and one C(1) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Ca(2) and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca4Tl2CO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.870
_cell_length_b   9.870
_cell_length_c   9.870
_cell_angle_alpha   151.668
_cell_angle_beta   151.210
_cell_angle_gamma   40.834
_symmetry_Int_Tables_number   1
_cell_volume   219.271
_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  0.608  0.102  0.494  1.0
  Ca  Ca1  1  0.111  0.588  0.477  1.0
  Ca  Ca2  1  0.392  0.886  0.494  1.0
  Ca  Ca3  1  0.889  0.366  0.477  1.0
  Tl  Tl4  1  0.254  0.245  0.992  1.0
  Tl  Tl5  1  0.746  0.738  0.992  1.0
  C  C6  1  0.000  0.974  0.974  1.0
  O  O7  1  0.629  0.621  0.992  1.0
  O  O8  1  0.371  0.363  0.992  1.0
  O  O9  1  0.138  0.124  0.986  1.0
  O  O10  1  0.862  0.848  0.986  1.0
  O  O11  1  0.750  0.241  0.491  1.0
  O  O12  1  0.250  0.741  0.491  1.0
  O  O13  1  0.772  0.109  0.881  1.0
  O  O14  1  0.228  0.109  0.337  1.0
  O  O15  1  0.000  0.705  0.705  1.0
[/CIF]
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