The compound described by MgDy2Nb2O8 crystallizes in the monoclinic C2 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Dy sites. In the first Dy site, Dy(1) 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. In the second Dy site, Dy(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. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a distorted trigonal pyramidal geometry to two equivalent O(1) and two equivalent O(2) atoms. In the second Nb site, Nb(2) is bonded in a distorted trigonal pyramidal geometry to two equivalent O(3) and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Dy(1), one Dy(2), and one Nb(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Dy(1), one Dy(2), and one Nb(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Dy(1), one Dy(2), and one Nb(2) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Dy(1), one Dy(2), and one Nb(2) atom to form a mixture of distorted corner and edge-sharing ODy2MgNb trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Dy2MgNb2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.202
_cell_length_b   6.202
_cell_length_c   6.116
_cell_angle_alpha   106.428
_cell_angle_beta   106.428
_cell_angle_gamma   113.629
_symmetry_Int_Tables_number   1
_cell_volume   184.538
_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
  Dy  Dy0  1  0.665  0.335  0.250  1.0
  Dy  Dy1  1  0.367  0.633  0.750  1.0
  Mg  Mg2  1  0.374  0.626  0.250  1.0
  Nb  Nb3  1  0.898  0.102  0.750  1.0
  Nb  Nb4  1  0.087  0.913  0.250  1.0
  O  O5  1  0.649  0.092  0.884  1.0
  O  O6  1  0.281  0.317  0.943  1.0
  O  O7  1  0.908  0.351  0.616  1.0
  O  O8  1  0.683  0.719  0.557  1.0
  O  O9  1  0.270  0.283  0.398  1.0
  O  O10  1  0.717  0.730  0.102  1.0
  O  O11  1  0.109  0.644  0.371  1.0
  O  O12  1  0.356  0.891  0.129  1.0
[/CIF]
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The compound described by MgDy2Nb2O8 crystallizes in the monoclinic C2 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Dy sites. In the first Dy site, Dy(1) 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. In the second Dy site, Dy(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. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a distorted trigonal pyramidal geometry to two equivalent O(1) and two equivalent O(2) atoms. In the second Nb site, Nb(2) is bonded in a distorted trigonal pyramidal geometry to two equivalent O(3) and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Dy(1), one Dy(2), and one Nb(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Dy(1), one Dy(2), and one Nb(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Dy(1), one Dy(2), and one Nb(2) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Dy(1), one Dy(2), and one Nb(2) atom to form a mixture of distorted corner and edge-sharing ODy2MgNb trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Dy2MgNb2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.202
_cell_length_b   6.202
_cell_length_c   6.116
_cell_angle_alpha   106.428
_cell_angle_beta   106.428
_cell_angle_gamma   113.629
_symmetry_Int_Tables_number   1
_cell_volume   184.538
_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
  Dy  Dy0  1  0.665  0.335  0.250  1.0
  Dy  Dy1  1  0.367  0.633  0.750  1.0
  Mg  Mg2  1  0.374  0.626  0.250  1.0
  Nb  Nb3  1  0.898  0.102  0.750  1.0
  Nb  Nb4  1  0.087  0.913  0.250  1.0
  O  O5  1  0.649  0.092  0.884  1.0
  O  O6  1  0.281  0.317  0.943  1.0
  O  O7  1  0.908  0.351  0.616  1.0
  O  O8  1  0.683  0.719  0.557  1.0
  O  O9  1  0.270  0.283  0.398  1.0
  O  O10  1  0.717  0.730  0.102  1.0
  O  O11  1  0.109  0.644  0.371  1.0
  O  O12  1  0.356  0.891  0.129  1.0
[/CIF]
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