The structure described by MgCu3(TeO5)2 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form MgO6 octahedra that share edges with two equivalent Cu(2)O6 octahedra and edges with four equivalent Te(1)O6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. In the second Cu site, Cu(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form distorted CuO6 octahedra that share  an edgeedge with one Mg(1)O6 octahedra, edges with two equivalent Cu(2)O6 octahedra, and edges with three equivalent Te(1)O6 octahedra. Te(1) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form TeO6 octahedra that share  an edgeedge with one Te(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with three equivalent Cu(2)O6 octahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to two equivalent Cu(2) and one Te(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Cu(1), two equivalent Cu(2), and one Te(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent Te(1) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cu(1), one Cu(2), and one Te(1) atom. In the fifth O site, O(5) is bonded in a trigonal non-coplanar geometry to one Mg(1), one Cu(2), and one Te(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCu3(TeO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.342
_cell_length_b   5.969
_cell_length_c   7.616
_cell_angle_alpha   104.986
_cell_angle_beta   101.159
_cell_angle_gamma   105.721
_symmetry_Int_Tables_number   1
_cell_volume   216.527
_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
  Mg  Mg0  1  0.500  0.500  0.500  1.0
  Cu  Cu1  1  0.000  0.500  0.000  1.0
  Cu  Cu2  1  0.696  0.876  0.909  1.0
  Cu  Cu3  1  0.304  0.124  0.091  1.0
  Te  Te4  1  0.115  0.704  0.705  1.0
  Te  Te5  1  0.885  0.296  0.295  1.0
  O  O6  1  0.067  0.010  0.832  1.0
  O  O7  1  0.322  0.692  0.942  1.0
  O  O8  1  0.126  0.355  0.545  1.0
  O  O9  1  0.200  0.480  0.235  1.0
  O  O10  1  0.462  0.822  0.662  1.0
  O  O11  1  0.538  0.178  0.338  1.0
  O  O12  1  0.800  0.520  0.765  1.0
  O  O13  1  0.874  0.645  0.455  1.0
  O  O14  1  0.678  0.308  0.058  1.0
  O  O15  1  0.933  0.990  0.168  1.0
[/CIF]
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The structure described by MgCu3(TeO5)2 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form MgO6 octahedra that share edges with two equivalent Cu(2)O6 octahedra and edges with four equivalent Te(1)O6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. In the second Cu site, Cu(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form distorted CuO6 octahedra that share  an edgeedge with one Mg(1)O6 octahedra, edges with two equivalent Cu(2)O6 octahedra, and edges with three equivalent Te(1)O6 octahedra. Te(1) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form TeO6 octahedra that share  an edgeedge with one Te(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with three equivalent Cu(2)O6 octahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to two equivalent Cu(2) and one Te(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Cu(1), two equivalent Cu(2), and one Te(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1) and two equivalent Te(1) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Cu(1), one Cu(2), and one Te(1) atom. In the fifth O site, O(5) is bonded in a trigonal non-coplanar geometry to one Mg(1), one Cu(2), and one Te(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCu3(TeO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.342
_cell_length_b   5.969
_cell_length_c   7.616
_cell_angle_alpha   104.986
_cell_angle_beta   101.159
_cell_angle_gamma   105.721
_symmetry_Int_Tables_number   1
_cell_volume   216.527
_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
  Mg  Mg0  1  0.500  0.500  0.500  1.0
  Cu  Cu1  1  0.000  0.500  0.000  1.0
  Cu  Cu2  1  0.696  0.876  0.909  1.0
  Cu  Cu3  1  0.304  0.124  0.091  1.0
  Te  Te4  1  0.115  0.704  0.705  1.0
  Te  Te5  1  0.885  0.296  0.295  1.0
  O  O6  1  0.067  0.010  0.832  1.0
  O  O7  1  0.322  0.692  0.942  1.0
  O  O8  1  0.126  0.355  0.545  1.0
  O  O9  1  0.200  0.480  0.235  1.0
  O  O10  1  0.462  0.822  0.662  1.0
  O  O11  1  0.538  0.178  0.338  1.0
  O  O12  1  0.800  0.520  0.765  1.0
  O  O13  1  0.874  0.645  0.455  1.0
  O  O14  1  0.678  0.308  0.058  1.0
  O  O15  1  0.933  0.990  0.168  1.0
[/CIF]
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