The compound described by Ba2MgY2(Fe2O5)2 crystallizes in the monoclinic Pm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to one O(5), one O(7), two equivalent O(10), and two equivalent O(9) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(10), two equivalent O(3), and two equivalent O(9) atoms. Mg(1) is bonded to one O(6), one O(8), and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with two equivalent Y(2)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, and edges with two equivalent Fe(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 1-46°. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 6-coordinate geometry to one O(5), one O(6), one O(7), one O(8), and two equivalent O(3) atoms. In the second Y site, Y(2) is bonded to one O(6), one O(8), two equivalent O(1), and two equivalent O(2) atoms to form YO6 octahedra that share corners with two equivalent Mg(1)O4 tetrahedra, edges with two equivalent Y(2)O6 octahedra, and edges with two equivalent Fe(2)O5 trigonal bipyramids. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(7) atoms. In the second Fe site, Fe(2) is bonded to one O(10), one O(2), one O(4), and two equivalent O(8) atoms to form FeO5 trigonal bipyramids that share corners with two equivalent Fe(2)O5 trigonal bipyramids, edges with two equivalent Y(2)O6 octahedra, and edges with two equivalent Mg(1)O4 tetrahedra. In the third Fe site, Fe(3) is bonded in a distorted trigonal planar geometry to one O(2), one O(4), and one O(9) atom. In the fourth Fe site, Fe(4) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(5) atoms. There are ten inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Y(2), one Fe(1), and one Fe(4) atom to form OY2Fe2 tetrahedra that share corners with two equivalent O(1)Y2Fe2 tetrahedra, corners with two equivalent O(2)Y2Fe2 tetrahedra, corners with two equivalent O(7)Ba2YFe2 trigonal bipyramids, and  an edgeedge with one O(2)Y2Fe2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Y(2), one Fe(2), and one Fe(3) atom to form a mixture of corner and edge-sharing OY2Fe2 tetrahedra. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Y(1), one Fe(1), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1), one Fe(2), and one Fe(3) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Y(1), and two equivalent Fe(4) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one Y(1), and one Y(2) atom. In the seventh O site, O(7) is bonded to one Ba(1), one Ba(2), one Y(1), and two equivalent Fe(1) atoms to form distorted OBa2YFe2 trigonal bipyramids that share corners with two equivalent O(1)Y2Fe2 tetrahedra and corners with two equivalent O(7)Ba2YFe2 trigonal bipyramids. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Mg(1), one Y(1), one Y(2), and two equivalent Fe(2) atoms. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and one Fe(3) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and one Fe(2) atom. is represented by the CIF file [CIF]
data_Ba2Y2Mg(Fe2O5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.793
_cell_length_b   10.087
_cell_length_c   7.688
_cell_angle_alpha   89.819
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   294.091
_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  0.000  0.959  0.519  1.0
  Ba  Ba1  1  0.000  0.954  0.002  1.0
  Y  Y2  1  0.000  0.608  0.011  1.0
  Y  Y3  1  0.000  0.440  0.482  1.0
  Mg  Mg4  1  0.000  0.306  0.014  1.0
  Fe  Fe5  1  0.500  0.714  0.304  1.0
  Fe  Fe6  1  0.500  0.237  0.742  1.0
  Fe  Fe7  1  0.500  0.189  0.271  1.0
  Fe  Fe8  1  0.500  0.699  0.705  1.0
  O  O9  1  0.500  0.581  0.498  1.0
  O  O10  1  0.500  0.297  0.476  1.0
  O  O11  1  0.500  0.710  0.991  1.0
  O  O12  1  0.500  0.230  0.026  1.0
  O  O13  1  0.000  0.739  0.735  1.0
  O  O14  1  0.000  0.442  0.190  1.0
  O  O15  1  0.000  0.744  0.255  1.0
  O  O16  1  0.000  0.369  0.772  1.0
  O  O17  1  0.500  0.001  0.269  1.0
  O  O18  1  0.500  0.041  0.740  1.0
[/CIF]
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The compound described by Ba2MgY2(Fe2O5)2 crystallizes in the monoclinic Pm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to one O(5), one O(7), two equivalent O(10), and two equivalent O(9) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one O(5), one O(7), two equivalent O(10), two equivalent O(3), and two equivalent O(9) atoms. Mg(1) is bonded to one O(6), one O(8), and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with two equivalent Y(2)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, and edges with two equivalent Fe(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 1-46°. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 6-coordinate geometry to one O(5), one O(6), one O(7), one O(8), and two equivalent O(3) atoms. In the second Y site, Y(2) is bonded to one O(6), one O(8), two equivalent O(1), and two equivalent O(2) atoms to form YO6 octahedra that share corners with two equivalent Mg(1)O4 tetrahedra, edges with two equivalent Y(2)O6 octahedra, and edges with two equivalent Fe(2)O5 trigonal bipyramids. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(7) atoms. In the second Fe site, Fe(2) is bonded to one O(10), one O(2), one O(4), and two equivalent O(8) atoms to form FeO5 trigonal bipyramids that share corners with two equivalent Fe(2)O5 trigonal bipyramids, edges with two equivalent Y(2)O6 octahedra, and edges with two equivalent Mg(1)O4 tetrahedra. In the third Fe site, Fe(3) is bonded in a distorted trigonal planar geometry to one O(2), one O(4), and one O(9) atom. In the fourth Fe site, Fe(4) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(5) atoms. There are ten inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Y(2), one Fe(1), and one Fe(4) atom to form OY2Fe2 tetrahedra that share corners with two equivalent O(1)Y2Fe2 tetrahedra, corners with two equivalent O(2)Y2Fe2 tetrahedra, corners with two equivalent O(7)Ba2YFe2 trigonal bipyramids, and  an edgeedge with one O(2)Y2Fe2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Y(2), one Fe(2), and one Fe(3) atom to form a mixture of corner and edge-sharing OY2Fe2 tetrahedra. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Y(1), one Fe(1), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1), one Fe(2), and one Fe(3) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Y(1), and two equivalent Fe(4) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one Y(1), and one Y(2) atom. In the seventh O site, O(7) is bonded to one Ba(1), one Ba(2), one Y(1), and two equivalent Fe(1) atoms to form distorted OBa2YFe2 trigonal bipyramids that share corners with two equivalent O(1)Y2Fe2 tetrahedra and corners with two equivalent O(7)Ba2YFe2 trigonal bipyramids. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Mg(1), one Y(1), one Y(2), and two equivalent Fe(2) atoms. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and one Fe(3) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and one Fe(2) atom. is represented by the CIF file [CIF]
data_Ba2Y2Mg(Fe2O5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.793
_cell_length_b   10.087
_cell_length_c   7.688
_cell_angle_alpha   89.819
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   294.091
_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  0.000  0.959  0.519  1.0
  Ba  Ba1  1  0.000  0.954  0.002  1.0
  Y  Y2  1  0.000  0.608  0.011  1.0
  Y  Y3  1  0.000  0.440  0.482  1.0
  Mg  Mg4  1  0.000  0.306  0.014  1.0
  Fe  Fe5  1  0.500  0.714  0.304  1.0
  Fe  Fe6  1  0.500  0.237  0.742  1.0
  Fe  Fe7  1  0.500  0.189  0.271  1.0
  Fe  Fe8  1  0.500  0.699  0.705  1.0
  O  O9  1  0.500  0.581  0.498  1.0
  O  O10  1  0.500  0.297  0.476  1.0
  O  O11  1  0.500  0.710  0.991  1.0
  O  O12  1  0.500  0.230  0.026  1.0
  O  O13  1  0.000  0.739  0.735  1.0
  O  O14  1  0.000  0.442  0.190  1.0
  O  O15  1  0.000  0.744  0.255  1.0
  O  O16  1  0.000  0.369  0.772  1.0
  O  O17  1  0.500  0.001  0.269  1.0
  O  O18  1  0.500  0.041  0.740  1.0
[/CIF]
.