The structure described by Be2CoTl2(O3F4)2 crystallizes in the monoclinic P2_1/c space group. Be(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form BeF4 tetrahedra that share corners with four equivalent Tl(1)OF4 trigonal bipyramids. Co(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CoO6 octahedra that share corners with two equivalent Tl(1)OF4 trigonal bipyramids. Tl(1) is bonded to one O(3), one F(1), one F(2), one F(3), and one F(4) atom to form TlOF4 trigonal bipyramids that share  a cornercorner with one Co(1)O6 octahedra and corners with four equivalent Be(1)F4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Co(1) and one O(2) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Co(1) and one O(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Co(1) and one Tl(1) atom. There are four inequivalent F sites. In the first F site, F(4) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom. In the second F site, F(1) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom. In the third F site, F(2) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom. In the fourth F site, F(3) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom. is represented by the CIF card [CIF]
data_Be2Tl2Co(O3F4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.775
_cell_length_b   10.644
_cell_length_c   9.777
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   106.614
_symmetry_Int_Tables_number   1
_cell_volume   575.894
_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
  Be  Be0  1  0.774  0.587  0.859  1.0
  Be  Be1  1  0.226  0.413  0.141  1.0
  Be  Be2  1  0.226  0.913  0.359  1.0
  Be  Be3  1  0.774  0.087  0.641  1.0
  Tl  Tl4  1  0.843  0.612  0.215  1.0
  Tl  Tl5  1  0.157  0.388  0.785  1.0
  Tl  Tl6  1  0.157  0.888  0.715  1.0
  Tl  Tl7  1  0.843  0.112  0.285  1.0
  Co  Co8  1  0.500  0.000  0.000  1.0
  Co  Co9  1  0.500  0.500  0.500  1.0
  O  O10  1  0.764  0.930  0.971  1.0
  O  O11  1  0.236  0.070  0.029  1.0
  O  O12  1  0.236  0.570  0.471  1.0
  O  O13  1  0.764  0.430  0.529  1.0
  O  O14  1  0.355  0.622  0.581  1.0
  O  O15  1  0.645  0.378  0.419  1.0
  O  O16  1  0.645  0.878  0.081  1.0
  O  O17  1  0.355  0.122  0.919  1.0
  O  O18  1  0.334  0.867  0.894  1.0
  O  O19  1  0.666  0.133  0.106  1.0
  O  O20  1  0.666  0.633  0.394  1.0
  O  O21  1  0.334  0.367  0.606  1.0
  F  F22  1  0.911  0.676  0.740  1.0
  F  F23  1  0.089  0.324  0.260  1.0
  F  F24  1  0.089  0.824  0.240  1.0
  F  F25  1  0.911  0.176  0.760  1.0
  F  F26  1  0.848  0.661  0.999  1.0
  F  F27  1  0.152  0.339  0.001  1.0
  F  F28  1  0.152  0.839  0.499  1.0
  F  F29  1  0.848  0.161  0.501  1.0
  F  F30  1  0.850  0.955  0.647  1.0
  F  F31  1  0.150  0.045  0.353  1.0
  F  F32  1  0.150  0.545  0.147  1.0
  F  F33  1  0.850  0.455  0.853  1.0
  F  F34  1  0.496  0.555  0.843  1.0
  F  F35  1  0.504  0.445  0.157  1.0
  F  F36  1  0.504  0.945  0.343  1.0
  F  F37  1  0.496  0.055  0.657  1.0
[/CIF]
.
The structure described by Be2CoTl2(O3F4)2 crystallizes in the monoclinic P2_1/c space group. Be(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form BeF4 tetrahedra that share corners with four equivalent Tl(1)OF4 trigonal bipyramids. Co(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CoO6 octahedra that share corners with two equivalent Tl(1)OF4 trigonal bipyramids. Tl(1) is bonded to one O(3), one F(1), one F(2), one F(3), and one F(4) atom to form TlOF4 trigonal bipyramids that share  a cornercorner with one Co(1)O6 octahedra and corners with four equivalent Be(1)F4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Co(1) and one O(2) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Co(1) and one O(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Co(1) and one Tl(1) atom. There are four inequivalent F sites. In the first F site, F(4) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom. In the second F site, F(1) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom. In the third F site, F(2) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom. In the fourth F site, F(3) is bonded in a distorted bent 150 degrees geometry to one Be(1) and one Tl(1) atom. is represented by the CIF card [CIF]
data_Be2Tl2Co(O3F4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.775
_cell_length_b   10.644
_cell_length_c   9.777
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   106.614
_symmetry_Int_Tables_number   1
_cell_volume   575.894
_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
  Be  Be0  1  0.774  0.587  0.859  1.0
  Be  Be1  1  0.226  0.413  0.141  1.0
  Be  Be2  1  0.226  0.913  0.359  1.0
  Be  Be3  1  0.774  0.087  0.641  1.0
  Tl  Tl4  1  0.843  0.612  0.215  1.0
  Tl  Tl5  1  0.157  0.388  0.785  1.0
  Tl  Tl6  1  0.157  0.888  0.715  1.0
  Tl  Tl7  1  0.843  0.112  0.285  1.0
  Co  Co8  1  0.500  0.000  0.000  1.0
  Co  Co9  1  0.500  0.500  0.500  1.0
  O  O10  1  0.764  0.930  0.971  1.0
  O  O11  1  0.236  0.070  0.029  1.0
  O  O12  1  0.236  0.570  0.471  1.0
  O  O13  1  0.764  0.430  0.529  1.0
  O  O14  1  0.355  0.622  0.581  1.0
  O  O15  1  0.645  0.378  0.419  1.0
  O  O16  1  0.645  0.878  0.081  1.0
  O  O17  1  0.355  0.122  0.919  1.0
  O  O18  1  0.334  0.867  0.894  1.0
  O  O19  1  0.666  0.133  0.106  1.0
  O  O20  1  0.666  0.633  0.394  1.0
  O  O21  1  0.334  0.367  0.606  1.0
  F  F22  1  0.911  0.676  0.740  1.0
  F  F23  1  0.089  0.324  0.260  1.0
  F  F24  1  0.089  0.824  0.240  1.0
  F  F25  1  0.911  0.176  0.760  1.0
  F  F26  1  0.848  0.661  0.999  1.0
  F  F27  1  0.152  0.339  0.001  1.0
  F  F28  1  0.152  0.839  0.499  1.0
  F  F29  1  0.848  0.161  0.501  1.0
  F  F30  1  0.850  0.955  0.647  1.0
  F  F31  1  0.150  0.045  0.353  1.0
  F  F32  1  0.150  0.545  0.147  1.0
  F  F33  1  0.850  0.455  0.853  1.0
  F  F34  1  0.496  0.555  0.843  1.0
  F  F35  1  0.504  0.445  0.157  1.0
  F  F36  1  0.504  0.945  0.343  1.0
  F  F37  1  0.496  0.055  0.657  1.0
[/CIF]
.