The compound described by MgTb2(NiO3)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(6) atom to form MgO5 trigonal bipyramids that share corners with three equivalent Ni(2)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, and edges with two equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 18-72°. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the second Tb site, Tb(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(3), one O(4), one O(5), and one O(6) atom to form NiO5 trigonal bipyramids that share corners with three equivalent Ni(2)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 18-76°. In the second Ni site, Ni(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form NiO6 octahedra that share corners with three equivalent Mg(1)O5 trigonal bipyramids, corners with three equivalent Ni(1)O5 trigonal bipyramids,  an edgeedge with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Ni(1)O5 trigonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom to form a mixture of corner and edge-sharing OTb2MgNi2 trigonal bipyramids. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Tb(1), one Tb(2), and one Ni(2) atom. In the third O site, O(3) is bonded to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom to form a mixture of corner and edge-sharing OTb2MgNi2 trigonal bipyramids. In the fourth O site, O(4) is bonded to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom to form a mixture of corner and edge-sharing OTb2MgNi2 trigonal bipyramids. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom to form a mixture of distorted corner and edge-sharing OTb2MgNi2 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb2Mg(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.689
_cell_length_b   5.690
_cell_length_c   5.959
_cell_angle_alpha   53.829
_cell_angle_beta   58.793
_cell_angle_gamma   72.956
_symmetry_Int_Tables_number   1
_cell_volume   133.149
_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  0.319  0.108  0.259  1.0
  Tb  Tb1  1  0.679  0.809  0.798  1.0
  Mg  Mg2  1  0.059  0.681  0.186  1.0
  Ni  Ni3  1  0.927  0.249  0.862  1.0
  Ni  Ni4  1  0.494  0.458  0.533  1.0
  O  O5  1  0.084  0.666  0.527  1.0
  O  O6  1  0.363  0.591  0.851  1.0
  O  O7  1  0.711  0.842  0.149  1.0
  O  O8  1  0.280  0.078  0.907  1.0
  O  O9  1  0.631  0.326  0.216  1.0
  O  O10  1  0.916  0.255  0.524  1.0
[/CIF]
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The compound described by MgTb2(NiO3)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(6) atom to form MgO5 trigonal bipyramids that share corners with three equivalent Ni(2)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, and edges with two equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 18-72°. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the second Tb site, Tb(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(3), one O(4), one O(5), and one O(6) atom to form NiO5 trigonal bipyramids that share corners with three equivalent Ni(2)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 18-76°. In the second Ni site, Ni(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form NiO6 octahedra that share corners with three equivalent Mg(1)O5 trigonal bipyramids, corners with three equivalent Ni(1)O5 trigonal bipyramids,  an edgeedge with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Ni(1)O5 trigonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom to form a mixture of corner and edge-sharing OTb2MgNi2 trigonal bipyramids. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Tb(1), one Tb(2), and one Ni(2) atom. In the third O site, O(3) is bonded to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom to form a mixture of corner and edge-sharing OTb2MgNi2 trigonal bipyramids. In the fourth O site, O(4) is bonded to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom to form a mixture of corner and edge-sharing OTb2MgNi2 trigonal bipyramids. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Tb(1), one Tb(2), one Ni(1), and one Ni(2) atom to form a mixture of distorted corner and edge-sharing OTb2MgNi2 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb2Mg(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.689
_cell_length_b   5.690
_cell_length_c   5.959
_cell_angle_alpha   53.829
_cell_angle_beta   58.793
_cell_angle_gamma   72.956
_symmetry_Int_Tables_number   1
_cell_volume   133.149
_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  0.319  0.108  0.259  1.0
  Tb  Tb1  1  0.679  0.809  0.798  1.0
  Mg  Mg2  1  0.059  0.681  0.186  1.0
  Ni  Ni3  1  0.927  0.249  0.862  1.0
  Ni  Ni4  1  0.494  0.458  0.533  1.0
  O  O5  1  0.084  0.666  0.527  1.0
  O  O6  1  0.363  0.591  0.851  1.0
  O  O7  1  0.711  0.842  0.149  1.0
  O  O8  1  0.280  0.078  0.907  1.0
  O  O9  1  0.631  0.326  0.216  1.0
  O  O10  1  0.916  0.255  0.524  1.0
[/CIF]
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