The compound described by Mg2Cu2O5 crystallizes in the orthorhombic Pbam space group. Mg(1) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(2), and three equivalent O(3) atoms. Cu(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing CuO5 square pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Mg(1) and two equivalent Cu(1) atoms to form OMg4Cu2 octahedra that share corners with eight equivalent O(2)Mg2Cu2 tetrahedra, corners with four equivalent O(3)Mg3Cu2 trigonal bipyramids, edges with two equivalent O(1)Mg4Cu2 octahedra, edges with two equivalent O(2)Mg2Cu2 tetrahedra, and faces with four equivalent O(3)Mg3Cu2 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Mg(1) and two equivalent Cu(1) atoms to form OMg2Cu2 tetrahedra that share corners with four equivalent O(1)Mg4Cu2 octahedra, corners with four equivalent O(2)Mg2Cu2 tetrahedra, corners with six equivalent O(3)Mg3Cu2 trigonal bipyramids,  an edgeedge with one O(1)Mg4Cu2 octahedra, and edges with two equivalent O(3)Mg3Cu2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 12-59°. In the third O site, O(3) is bonded to three equivalent Mg(1) and two equivalent Cu(1) atoms to form distorted OMg3Cu2 trigonal bipyramids that share corners with two equivalent O(1)Mg4Cu2 octahedra, corners with six equivalent O(2)Mg2Cu2 tetrahedra, corners with four equivalent O(3)Mg3Cu2 trigonal bipyramids, edges with two equivalent O(2)Mg2Cu2 tetrahedra, edges with two equivalent O(3)Mg3Cu2 trigonal bipyramids, and faces with two equivalent O(1)Mg4Cu2 octahedra. The corner-sharing octahedral tilt angles are 64°. is represented by the CIF file [CIF]
data_Mg2Cu2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.751
_cell_length_b   4.756
_cell_length_c   10.305
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   183.850
_cell_formula_units_Z   2
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
  Mg  Mg0  1  0.000  0.711  0.901  1.0
  Mg  Mg1  1  0.000  0.289  0.099  1.0
  Mg  Mg2  1  0.000  0.211  0.599  1.0
  Mg  Mg3  1  0.000  0.789  0.401  1.0
  Cu  Cu4  1  0.500  0.713  0.634  1.0
  Cu  Cu5  1  0.500  0.287  0.366  1.0
  Cu  Cu6  1  0.500  0.787  0.134  1.0
  Cu  Cu7  1  0.500  0.213  0.866  1.0
  O  O8  1  0.500  0.000  0.500  1.0
  O  O9  1  0.500  0.678  0.326  1.0
  O  O10  1  0.500  0.178  0.174  1.0
  O  O11  1  0.500  0.822  0.826  1.0
  O  O12  1  0.000  0.774  0.107  1.0
  O  O13  1  0.000  0.226  0.893  1.0
  O  O14  1  0.500  0.322  0.674  1.0
  O  O15  1  0.000  0.726  0.607  1.0
  O  O16  1  0.500  0.500  0.000  1.0
  O  O17  1  0.000  0.274  0.393  1.0
[/CIF]
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The compound described by Mg2Cu2O5 crystallizes in the orthorhombic Pbam space group. Mg(1) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(2), and three equivalent O(3) atoms. Cu(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing CuO5 square pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Mg(1) and two equivalent Cu(1) atoms to form OMg4Cu2 octahedra that share corners with eight equivalent O(2)Mg2Cu2 tetrahedra, corners with four equivalent O(3)Mg3Cu2 trigonal bipyramids, edges with two equivalent O(1)Mg4Cu2 octahedra, edges with two equivalent O(2)Mg2Cu2 tetrahedra, and faces with four equivalent O(3)Mg3Cu2 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Mg(1) and two equivalent Cu(1) atoms to form OMg2Cu2 tetrahedra that share corners with four equivalent O(1)Mg4Cu2 octahedra, corners with four equivalent O(2)Mg2Cu2 tetrahedra, corners with six equivalent O(3)Mg3Cu2 trigonal bipyramids,  an edgeedge with one O(1)Mg4Cu2 octahedra, and edges with two equivalent O(3)Mg3Cu2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 12-59°. In the third O site, O(3) is bonded to three equivalent Mg(1) and two equivalent Cu(1) atoms to form distorted OMg3Cu2 trigonal bipyramids that share corners with two equivalent O(1)Mg4Cu2 octahedra, corners with six equivalent O(2)Mg2Cu2 tetrahedra, corners with four equivalent O(3)Mg3Cu2 trigonal bipyramids, edges with two equivalent O(2)Mg2Cu2 tetrahedra, edges with two equivalent O(3)Mg3Cu2 trigonal bipyramids, and faces with two equivalent O(1)Mg4Cu2 octahedra. The corner-sharing octahedral tilt angles are 64°. is represented by the CIF file [CIF]
data_Mg2Cu2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.751
_cell_length_b   4.756
_cell_length_c   10.305
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   183.850
_cell_formula_units_Z   2
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
  Mg  Mg0  1  0.000  0.711  0.901  1.0
  Mg  Mg1  1  0.000  0.289  0.099  1.0
  Mg  Mg2  1  0.000  0.211  0.599  1.0
  Mg  Mg3  1  0.000  0.789  0.401  1.0
  Cu  Cu4  1  0.500  0.713  0.634  1.0
  Cu  Cu5  1  0.500  0.287  0.366  1.0
  Cu  Cu6  1  0.500  0.787  0.134  1.0
  Cu  Cu7  1  0.500  0.213  0.866  1.0
  O  O8  1  0.500  0.000  0.500  1.0
  O  O9  1  0.500  0.678  0.326  1.0
  O  O10  1  0.500  0.178  0.174  1.0
  O  O11  1  0.500  0.822  0.826  1.0
  O  O12  1  0.000  0.774  0.107  1.0
  O  O13  1  0.000  0.226  0.893  1.0
  O  O14  1  0.500  0.322  0.674  1.0
  O  O15  1  0.000  0.726  0.607  1.0
  O  O16  1  0.500  0.500  0.000  1.0
  O  O17  1  0.000  0.274  0.393  1.0
[/CIF]
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