The material structure described by MgTb2(NiO3)2 crystallizes in the trigonal R3 space group. Mg(1) is bonded in a distorted trigonal non-coplanar geometry to three equivalent O(1) and three equivalent O(2) atoms. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form TbO6 octahedra that share corners with three equivalent Ni(1)O6 octahedra and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. In the second Tb site, Tb(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NiO6 octahedra that share corners with three equivalent Tb(1)O6 octahedra and  a faceface with one Tb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. In the second Ni site, Ni(2) is bonded in a trigonal planar geometry to three equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Tb(1), one Tb(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OTb2MgNi trigonal pyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb2Mg(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.211
_cell_length_b   6.211
_cell_length_c   6.211
_cell_angle_alpha   53.346
_cell_angle_beta   53.345
_cell_angle_gamma   53.345
_symmetry_Int_Tables_number   1
_cell_volume   143.020
_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
  Tb  Tb0  1  0.172  0.172  0.172  1.0
  Tb  Tb1  1  0.800  0.800  0.799  1.0
  Mg  Mg2  1  0.367  0.367  0.367  1.0
  Ni  Ni3  1  0.992  0.992  0.992  1.0
  Ni  Ni4  1  0.572  0.572  0.572  1.0
  O  O5  1  0.097  0.761  0.375  1.0
  O  O6  1  0.220  0.606  0.914  1.0
  O  O7  1  0.606  0.914  0.220  1.0
  O  O8  1  0.375  0.097  0.761  1.0
  O  O9  1  0.761  0.375  0.097  1.0
  O  O10  1  0.914  0.220  0.606  1.0
[/CIF]
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The material structure described by MgTb2(NiO3)2 crystallizes in the trigonal R3 space group. Mg(1) is bonded in a distorted trigonal non-coplanar geometry to three equivalent O(1) and three equivalent O(2) atoms. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form TbO6 octahedra that share corners with three equivalent Ni(1)O6 octahedra and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. In the second Tb site, Tb(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NiO6 octahedra that share corners with three equivalent Tb(1)O6 octahedra and  a faceface with one Tb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. In the second Ni site, Ni(2) is bonded in a trigonal planar geometry to three equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Tb(1), one Tb(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OTb2MgNi trigonal pyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb2Mg(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.211
_cell_length_b   6.211
_cell_length_c   6.211
_cell_angle_alpha   53.346
_cell_angle_beta   53.345
_cell_angle_gamma   53.345
_symmetry_Int_Tables_number   1
_cell_volume   143.020
_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
  Tb  Tb0  1  0.172  0.172  0.172  1.0
  Tb  Tb1  1  0.800  0.800  0.799  1.0
  Mg  Mg2  1  0.367  0.367  0.367  1.0
  Ni  Ni3  1  0.992  0.992  0.992  1.0
  Ni  Ni4  1  0.572  0.572  0.572  1.0
  O  O5  1  0.097  0.761  0.375  1.0
  O  O6  1  0.220  0.606  0.914  1.0
  O  O7  1  0.606  0.914  0.220  1.0
  O  O8  1  0.375  0.097  0.761  1.0
  O  O9  1  0.761  0.375  0.097  1.0
  O  O10  1  0.914  0.220  0.606  1.0
[/CIF]
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