The structure described by Sr4Tl2CO9 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(2), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form SrO7 pentagonal bipyramids that share corners with four equivalent Sr(1)O7 pentagonal bipyramids, edges with four equivalent Tl(1)O6 octahedra, and  an edgeedge with one Sr(1)O7 pentagonal bipyramid. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(2), one O(5), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. Tl(1) is bonded to one O(1), one O(3), and four equivalent O(2) 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 Sr(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 2-3°. 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 Sr(1), two equivalent Sr(2), and one Tl(1) atom to form distorted OSr4Tl trigonal bipyramids that share  a cornercorner with one O(3)Sr4Tl square pyramid, corners with four equivalent O(1)Sr4Tl trigonal bipyramids, edges with four equivalent O(2)Sr2Tl4 octahedra, and edges with four equivalent O(3)Sr4Tl square pyramids. In the second O site, O(2) is bonded to one Sr(1), one Sr(2), and four equivalent Tl(1) atoms to form OSr2Tl4 octahedra that share corners with four equivalent O(2)Sr2Tl4 octahedra, edges with four equivalent O(2)Sr2Tl4 octahedra, edges with four equivalent O(3)Sr4Tl square pyramids, and edges with four equivalent O(1)Sr4Tl trigonal bipyramids. The corner-sharing octahedral tilt angles range from 2-3°. In the third O site, O(3) is bonded to two equivalent Sr(1), two equivalent Sr(2), and one Tl(1) atom to form OSr4Tl square pyramids that share corners with four equivalent O(3)Sr4Tl square pyramids,  a cornercorner with one O(1)Sr4Tl trigonal bipyramid, edges with four equivalent O(2)Sr2Tl4 octahedra, and edges with four equivalent O(1)Sr4Tl trigonal bipyramids. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(2), and one C(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Sr(2) and one C(1) atom. is represented by the CIF card [CIF]
data_Sr4Tl2CO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.130
_cell_length_b   5.083
_cell_length_c   10.203
_cell_angle_alpha   75.576
_cell_angle_beta   75.441
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   248.851
_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
  Sr  Sr0  1  0.611  0.122  0.777  1.0
  Sr  Sr1  1  0.113  0.639  0.773  1.0
  Sr  Sr2  1  0.389  0.900  0.223  1.0
  Sr  Sr3  1  0.887  0.412  0.227  1.0
  Tl  Tl4  1  0.253  0.263  0.495  1.0
  Tl  Tl5  1  0.747  0.757  0.505  1.0
  C  C6  1  0.000  0.022  0.000  1.0
  O  O7  1  0.141  0.158  0.717  1.0
  O  O8  1  0.859  0.875  0.283  1.0
  O  O9  1  0.749  0.257  0.501  1.0
  O  O10  1  0.251  0.758  0.499  1.0
  O  O11  1  0.635  0.644  0.731  1.0
  O  O12  1  0.365  0.375  0.269  1.0
  O  O13  1  0.219  0.892  0.000  1.0
  O  O14  1  0.781  0.892  0.000  1.0
  O  O15  1  0.000  0.277  0.000  1.0
[/CIF]
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The structure described by Sr4Tl2CO9 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(2), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form SrO7 pentagonal bipyramids that share corners with four equivalent Sr(1)O7 pentagonal bipyramids, edges with four equivalent Tl(1)O6 octahedra, and  an edgeedge with one Sr(1)O7 pentagonal bipyramid. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(2), one O(5), two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. Tl(1) is bonded to one O(1), one O(3), and four equivalent O(2) 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 Sr(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 2-3°. 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 Sr(1), two equivalent Sr(2), and one Tl(1) atom to form distorted OSr4Tl trigonal bipyramids that share  a cornercorner with one O(3)Sr4Tl square pyramid, corners with four equivalent O(1)Sr4Tl trigonal bipyramids, edges with four equivalent O(2)Sr2Tl4 octahedra, and edges with four equivalent O(3)Sr4Tl square pyramids. In the second O site, O(2) is bonded to one Sr(1), one Sr(2), and four equivalent Tl(1) atoms to form OSr2Tl4 octahedra that share corners with four equivalent O(2)Sr2Tl4 octahedra, edges with four equivalent O(2)Sr2Tl4 octahedra, edges with four equivalent O(3)Sr4Tl square pyramids, and edges with four equivalent O(1)Sr4Tl trigonal bipyramids. The corner-sharing octahedral tilt angles range from 2-3°. In the third O site, O(3) is bonded to two equivalent Sr(1), two equivalent Sr(2), and one Tl(1) atom to form OSr4Tl square pyramids that share corners with four equivalent O(3)Sr4Tl square pyramids,  a cornercorner with one O(1)Sr4Tl trigonal bipyramid, edges with four equivalent O(2)Sr2Tl4 octahedra, and edges with four equivalent O(1)Sr4Tl trigonal bipyramids. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to two equivalent Sr(1), two equivalent Sr(2), and one C(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Sr(2) and one C(1) atom. is represented by the CIF card [CIF]
data_Sr4Tl2CO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.130
_cell_length_b   5.083
_cell_length_c   10.203
_cell_angle_alpha   75.576
_cell_angle_beta   75.441
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   248.851
_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
  Sr  Sr0  1  0.611  0.122  0.777  1.0
  Sr  Sr1  1  0.113  0.639  0.773  1.0
  Sr  Sr2  1  0.389  0.900  0.223  1.0
  Sr  Sr3  1  0.887  0.412  0.227  1.0
  Tl  Tl4  1  0.253  0.263  0.495  1.0
  Tl  Tl5  1  0.747  0.757  0.505  1.0
  C  C6  1  0.000  0.022  0.000  1.0
  O  O7  1  0.141  0.158  0.717  1.0
  O  O8  1  0.859  0.875  0.283  1.0
  O  O9  1  0.749  0.257  0.501  1.0
  O  O10  1  0.251  0.758  0.499  1.0
  O  O11  1  0.635  0.644  0.731  1.0
  O  O12  1  0.365  0.375  0.269  1.0
  O  O13  1  0.219  0.892  0.000  1.0
  O  O14  1  0.781  0.892  0.000  1.0
  O  O15  1  0.000  0.277  0.000  1.0
[/CIF]
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