The compound described by Ba2Mg3Tl2(NiO3)4 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(4) atoms. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a rectangular see-saw-like geometry to four equivalent O(2) atoms. In the second Ni site, Ni(2) is bonded in a rectangular see-saw-like geometry to four equivalent O(1) atoms. Tl(1) is bonded to one O(4) and five equivalent O(3) atoms to form a mixture of edge and corner-sharing TlO6 octahedra. The corner-sharing octahedral tilt angles are 9°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Mg(1), and two equivalent Ni(2) atoms to form distorted OBa2Mg2Ni2 octahedra that share corners with two equivalent O(1)Ba2Mg2Ni2 octahedra, corners with two equivalent O(3)BaTl5 octahedra, corners with six equivalent O(2)Mg4Ni2 octahedra,  an edgeedge with one O(2)Mg4Ni2 octahedra, edges with two equivalent O(1)Ba2Mg2Ni2 octahedra, and faces with four equivalent O(1)Ba2Mg2Ni2 octahedra. The corner-sharing octahedral tilt angles range from 3-69°. In the second O site, O(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), and two equivalent Ni(1) atoms to form distorted OMg4Ni2 octahedra that share corners with six equivalent O(1)Ba2Mg2Ni2 octahedra, corners with eight equivalent O(2)Mg4Ni2 octahedra,  an edgeedge with one O(1)Ba2Mg2Ni2 octahedra, edges with three equivalent O(2)Mg4Ni2 octahedra, and faces with four equivalent O(2)Mg4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the third O site, O(3) is bonded to one Ba(1) and five equivalent Tl(1) atoms to form distorted OBaTl5 octahedra that share corners with four equivalent O(1)Ba2Mg2Ni2 octahedra, corners with four equivalent O(3)BaTl5 octahedra, and edges with eight equivalent O(3)BaTl5 octahedra. The corner-sharing octahedral tilt angles range from 9-42°. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to four equivalent Ba(1) and one Tl(1) atom. is represented by the CIF card [CIF]
data_Ba2Mg3Tl2(NiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.735
_cell_length_b   3.735
_cell_length_c   21.102
_cell_angle_alpha   95.077
_cell_angle_beta   95.077
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   292.081
_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
  Ba  Ba0  1  0.152  0.152  0.305  1.0
  Ba  Ba1  1  0.848  0.848  0.695  1.0
  Mg  Mg2  1  0.072  0.072  0.144  1.0
  Mg  Mg3  1  0.928  0.928  0.856  1.0
  Mg  Mg4  1  0.000  0.000  0.000  1.0
  Tl  Tl5  1  0.722  0.722  0.444  1.0
  Tl  Tl6  1  0.278  0.278  0.556  1.0
  Ni  Ni7  1  0.535  0.535  0.071  1.0
  Ni  Ni8  1  0.397  0.397  0.794  1.0
  Ni  Ni9  1  0.603  0.603  0.206  1.0
  Ni  Ni10  1  0.465  0.465  0.929  1.0
  O  O11  1  0.398  0.898  0.796  1.0
  O  O12  1  0.534  0.034  0.067  1.0
  O  O13  1  0.227  0.227  0.454  1.0
  O  O14  1  0.966  0.466  0.933  1.0
  O  O15  1  0.773  0.773  0.546  1.0
  O  O16  1  0.102  0.602  0.204  1.0
  O  O17  1  0.602  0.102  0.204  1.0
  O  O18  1  0.327  0.327  0.655  1.0
  O  O19  1  0.898  0.398  0.796  1.0
  O  O20  1  0.034  0.534  0.067  1.0
  O  O21  1  0.466  0.966  0.933  1.0
  O  O22  1  0.673  0.673  0.345  1.0
[/CIF]
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The compound described by Ba2Mg3Tl2(NiO3)4 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(4) atoms. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a rectangular see-saw-like geometry to four equivalent O(2) atoms. In the second Ni site, Ni(2) is bonded in a rectangular see-saw-like geometry to four equivalent O(1) atoms. Tl(1) is bonded to one O(4) and five equivalent O(3) atoms to form a mixture of edge and corner-sharing TlO6 octahedra. The corner-sharing octahedral tilt angles are 9°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Mg(1), and two equivalent Ni(2) atoms to form distorted OBa2Mg2Ni2 octahedra that share corners with two equivalent O(1)Ba2Mg2Ni2 octahedra, corners with two equivalent O(3)BaTl5 octahedra, corners with six equivalent O(2)Mg4Ni2 octahedra,  an edgeedge with one O(2)Mg4Ni2 octahedra, edges with two equivalent O(1)Ba2Mg2Ni2 octahedra, and faces with four equivalent O(1)Ba2Mg2Ni2 octahedra. The corner-sharing octahedral tilt angles range from 3-69°. In the second O site, O(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), and two equivalent Ni(1) atoms to form distorted OMg4Ni2 octahedra that share corners with six equivalent O(1)Ba2Mg2Ni2 octahedra, corners with eight equivalent O(2)Mg4Ni2 octahedra,  an edgeedge with one O(1)Ba2Mg2Ni2 octahedra, edges with three equivalent O(2)Mg4Ni2 octahedra, and faces with four equivalent O(2)Mg4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-69°. In the third O site, O(3) is bonded to one Ba(1) and five equivalent Tl(1) atoms to form distorted OBaTl5 octahedra that share corners with four equivalent O(1)Ba2Mg2Ni2 octahedra, corners with four equivalent O(3)BaTl5 octahedra, and edges with eight equivalent O(3)BaTl5 octahedra. The corner-sharing octahedral tilt angles range from 9-42°. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to four equivalent Ba(1) and one Tl(1) atom. is represented by the CIF card [CIF]
data_Ba2Mg3Tl2(NiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.735
_cell_length_b   3.735
_cell_length_c   21.102
_cell_angle_alpha   95.077
_cell_angle_beta   95.077
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   292.081
_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
  Ba  Ba0  1  0.152  0.152  0.305  1.0
  Ba  Ba1  1  0.848  0.848  0.695  1.0
  Mg  Mg2  1  0.072  0.072  0.144  1.0
  Mg  Mg3  1  0.928  0.928  0.856  1.0
  Mg  Mg4  1  0.000  0.000  0.000  1.0
  Tl  Tl5  1  0.722  0.722  0.444  1.0
  Tl  Tl6  1  0.278  0.278  0.556  1.0
  Ni  Ni7  1  0.535  0.535  0.071  1.0
  Ni  Ni8  1  0.397  0.397  0.794  1.0
  Ni  Ni9  1  0.603  0.603  0.206  1.0
  Ni  Ni10  1  0.465  0.465  0.929  1.0
  O  O11  1  0.398  0.898  0.796  1.0
  O  O12  1  0.534  0.034  0.067  1.0
  O  O13  1  0.227  0.227  0.454  1.0
  O  O14  1  0.966  0.466  0.933  1.0
  O  O15  1  0.773  0.773  0.546  1.0
  O  O16  1  0.102  0.602  0.204  1.0
  O  O17  1  0.602  0.102  0.204  1.0
  O  O18  1  0.327  0.327  0.655  1.0
  O  O19  1  0.898  0.398  0.796  1.0
  O  O20  1  0.034  0.534  0.067  1.0
  O  O21  1  0.466  0.966  0.933  1.0
  O  O22  1  0.673  0.673  0.345  1.0
[/CIF]
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