The structure described by Ba2Mg(NiO3)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Mg(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted MgO5 trigonal bipyramids that share corners with four equivalent Ni(2)O5 square pyramids. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(1), and two equivalent O(3) atoms. In the second Ni site, Ni(2) is bonded to one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted NiO5 square pyramids that share corners with four equivalent Mg(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), one Ni(1), and one Ni(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and one Mg(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), one Ni(1), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Ba(1), two equivalent Ba(2), one Ni(1), and one Ni(2) atom. is represented by the CIF card [CIF]
data_Ba2Mg(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.277
_cell_length_b   5.505
_cell_length_c   5.455
_cell_angle_alpha   90.000
_cell_angle_beta   109.223
_cell_angle_gamma   116.010
_symmetry_Int_Tables_number   1
_cell_volume   157.633
_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  0.657  0.328  0.795  1.0
  Ba  Ba1  1  0.450  0.725  0.166  1.0
  Mg  Mg2  1  0.123  0.562  0.525  1.0
  Ni  Ni3  1  0.044  0.022  0.505  1.0
  Ni  Ni4  1  0.020  0.010  0.015  1.0
  O  O5  1  0.919  0.201  0.243  1.0
  O  O6  1  0.515  0.757  0.677  1.0
  O  O7  1  0.090  0.279  0.768  1.0
  O  O8  1  0.919  0.718  0.243  1.0
  O  O9  1  0.090  0.811  0.768  1.0
  O  O10  1  0.340  0.170  0.326  1.0
[/CIF]
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The structure described by Ba2Mg(NiO3)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Mg(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted MgO5 trigonal bipyramids that share corners with four equivalent Ni(2)O5 square pyramids. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(1), and two equivalent O(3) atoms. In the second Ni site, Ni(2) is bonded to one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted NiO5 square pyramids that share corners with four equivalent Mg(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), one Ni(1), and one Ni(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and one Mg(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), one Mg(1), one Ni(1), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Ba(1), two equivalent Ba(2), one Ni(1), and one Ni(2) atom. is represented by the CIF card [CIF]
data_Ba2Mg(NiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.277
_cell_length_b   5.505
_cell_length_c   5.455
_cell_angle_alpha   90.000
_cell_angle_beta   109.223
_cell_angle_gamma   116.010
_symmetry_Int_Tables_number   1
_cell_volume   157.633
_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  0.657  0.328  0.795  1.0
  Ba  Ba1  1  0.450  0.725  0.166  1.0
  Mg  Mg2  1  0.123  0.562  0.525  1.0
  Ni  Ni3  1  0.044  0.022  0.505  1.0
  Ni  Ni4  1  0.020  0.010  0.015  1.0
  O  O5  1  0.919  0.201  0.243  1.0
  O  O6  1  0.515  0.757  0.677  1.0
  O  O7  1  0.090  0.279  0.768  1.0
  O  O8  1  0.919  0.718  0.243  1.0
  O  O9  1  0.090  0.811  0.768  1.0
  O  O10  1  0.340  0.170  0.326  1.0
[/CIF]
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