The crystal structure described by Ba2MgEr(CuO2)4 crystallizes in the monoclinic P2/m space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. Mg(1) is bonded in a 4-coordinate geometry to four equivalent O(1) atoms. Er(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(4), two equivalent O(2), and two equivalent O(3) atoms. In the second Cu site, Cu(2) is bonded in a 4-coordinate geometry to one O(4) and three equivalent O(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Mg(1) and three equivalent Cu(2) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Er(1), and two equivalent Cu(1) atoms to form a mixture of distorted edge and corner-sharing OBa2Er2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Er(1), and two equivalent Cu(1) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Cu(1), and one Cu(2) atom. is represented by the CIF file [CIF]
data_Ba2ErMg(CuO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.740
_cell_length_b   3.979
_cell_length_c   15.044
_cell_angle_alpha   96.743
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   222.336
_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  0.500  0.388  0.754  1.0
  Ba  Ba1  1  0.500  0.612  0.246  1.0
  Er  Er2  1  0.500  0.500  0.000  1.0
  Mg  Mg3  1  0.500  0.500  0.500  1.0
  Cu  Cu4  1  0.000  0.951  0.894  1.0
  Cu  Cu5  1  0.000  0.049  0.106  1.0
  Cu  Cu6  1  0.000  0.839  0.591  1.0
  Cu  Cu7  1  0.000  0.161  0.409  1.0
  O  O8  1  0.000  0.296  0.553  1.0
  O  O9  1  0.000  0.704  0.447  1.0
  O  O10  1  0.000  0.455  0.903  1.0
  O  O11  1  0.000  0.545  0.097  1.0
  O  O12  1  0.500  0.956  0.906  1.0
  O  O13  1  0.500  0.044  0.094  1.0
  O  O14  1  0.000  0.871  0.716  1.0
  O  O15  1  0.000  0.129  0.284  1.0
[/CIF]
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The crystal structure described by Ba2MgEr(CuO2)4 crystallizes in the monoclinic P2/m space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. Mg(1) is bonded in a 4-coordinate geometry to four equivalent O(1) atoms. Er(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(4), two equivalent O(2), and two equivalent O(3) atoms. In the second Cu site, Cu(2) is bonded in a 4-coordinate geometry to one O(4) and three equivalent O(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Mg(1) and three equivalent Cu(2) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Er(1), and two equivalent Cu(1) atoms to form a mixture of distorted edge and corner-sharing OBa2Er2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Er(1), and two equivalent Cu(1) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to four equivalent Ba(1), one Cu(1), and one Cu(2) atom. is represented by the CIF file [CIF]
data_Ba2ErMg(CuO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.740
_cell_length_b   3.979
_cell_length_c   15.044
_cell_angle_alpha   96.743
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   222.336
_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  0.500  0.388  0.754  1.0
  Ba  Ba1  1  0.500  0.612  0.246  1.0
  Er  Er2  1  0.500  0.500  0.000  1.0
  Mg  Mg3  1  0.500  0.500  0.500  1.0
  Cu  Cu4  1  0.000  0.951  0.894  1.0
  Cu  Cu5  1  0.000  0.049  0.106  1.0
  Cu  Cu6  1  0.000  0.839  0.591  1.0
  Cu  Cu7  1  0.000  0.161  0.409  1.0
  O  O8  1  0.000  0.296  0.553  1.0
  O  O9  1  0.000  0.704  0.447  1.0
  O  O10  1  0.000  0.455  0.903  1.0
  O  O11  1  0.000  0.545  0.097  1.0
  O  O12  1  0.500  0.956  0.906  1.0
  O  O13  1  0.500  0.044  0.094  1.0
  O  O14  1  0.000  0.871  0.716  1.0
  O  O15  1  0.000  0.129  0.284  1.0
[/CIF]
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