The structure described by MgTi4(CuO4)3 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 6-coordinate geometry to one O(6), one O(7), two equivalent O(2), and two equivalent O(5) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(8) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 36-45°. In the second Ti site, Ti(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 36-45°. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to one O(3), one O(6), one O(7), and one O(8) atom. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. In the third Cu site, Cu(3) is bonded in a square co-planar geometry to two equivalent O(4) and two equivalent O(5) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ti(1), one Ti(2), and one Cu(2) atom. In the second O site, O(2) is bonded to one Mg(1), one Ti(1), one Ti(2), and one Cu(2) atom to form a mixture of distorted edge and corner-sharing OMgTi2Cu tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to two equivalent Ti(2) and one Cu(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ti(2), and one Cu(3) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Ti(1), one Ti(2), and one Cu(3) atom to form a mixture of distorted edge and corner-sharing OMgTi2Cu tetrahedra. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent Ti(1), and one Cu(1) atom to form a mixture of distorted edge and corner-sharing OMgTi2Cu trigonal pyramids. In the seventh O site, O(7) is bonded to one Mg(1), two equivalent Ti(2), and one Cu(1) atom to form edge-sharing OMgTi2Cu tetrahedra. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to two equivalent Ti(1) and one Cu(1) atom. is represented by the CIF file [CIF]
data_MgTi4(CuO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.423
_cell_length_b   6.483
_cell_length_c   6.423
_cell_angle_alpha   109.206
_cell_angle_beta   109.446
_cell_angle_gamma   109.388
_symmetry_Int_Tables_number   1
_cell_volume   206.855
_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  0.945  0.874  0.928  1.0
  Ti  Ti1  1  1.000  0.976  0.484  1.0
  Ti  Ti2  1  0.988  0.456  0.984  1.0
  Ti  Ti3  1  0.471  0.456  0.468  1.0
  Ti  Ti4  1  0.492  0.976  0.976  1.0
  Cu  Cu5  1  0.500  0.487  0.987  1.0
  Cu  Cu6  1  0.994  0.490  0.496  1.0
  Cu  Cu7  1  0.494  0.980  0.485  1.0
  O  O8  1  0.818  0.297  0.123  1.0
  O  O9  1  0.171  0.693  0.870  1.0
  O  O10  1  0.823  0.693  0.522  1.0
  O  O11  1  0.306  0.473  0.166  1.0
  O  O12  1  0.478  0.163  0.295  1.0
  O  O13  1  0.119  0.809  0.287  1.0
  O  O14  1  0.699  0.861  0.162  1.0
  O  O15  1  0.522  0.809  0.690  1.0
  O  O16  1  0.174  0.297  0.479  1.0
  O  O17  1  0.696  0.507  0.810  1.0
  O  O18  1  0.868  0.163  0.685  1.0
  O  O19  1  0.305  0.114  0.809  1.0
[/CIF]
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The structure described by MgTi4(CuO4)3 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 6-coordinate geometry to one O(6), one O(7), two equivalent O(2), and two equivalent O(5) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(8) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 36-45°. In the second Ti site, Ti(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 36-45°. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to one O(3), one O(6), one O(7), and one O(8) atom. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. In the third Cu site, Cu(3) is bonded in a square co-planar geometry to two equivalent O(4) and two equivalent O(5) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ti(1), one Ti(2), and one Cu(2) atom. In the second O site, O(2) is bonded to one Mg(1), one Ti(1), one Ti(2), and one Cu(2) atom to form a mixture of distorted edge and corner-sharing OMgTi2Cu tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to two equivalent Ti(2) and one Cu(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ti(2), and one Cu(3) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Ti(1), one Ti(2), and one Cu(3) atom to form a mixture of distorted edge and corner-sharing OMgTi2Cu tetrahedra. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent Ti(1), and one Cu(1) atom to form a mixture of distorted edge and corner-sharing OMgTi2Cu trigonal pyramids. In the seventh O site, O(7) is bonded to one Mg(1), two equivalent Ti(2), and one Cu(1) atom to form edge-sharing OMgTi2Cu tetrahedra. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to two equivalent Ti(1) and one Cu(1) atom. is represented by the CIF file [CIF]
data_MgTi4(CuO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.423
_cell_length_b   6.483
_cell_length_c   6.423
_cell_angle_alpha   109.206
_cell_angle_beta   109.446
_cell_angle_gamma   109.388
_symmetry_Int_Tables_number   1
_cell_volume   206.855
_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  0.945  0.874  0.928  1.0
  Ti  Ti1  1  1.000  0.976  0.484  1.0
  Ti  Ti2  1  0.988  0.456  0.984  1.0
  Ti  Ti3  1  0.471  0.456  0.468  1.0
  Ti  Ti4  1  0.492  0.976  0.976  1.0
  Cu  Cu5  1  0.500  0.487  0.987  1.0
  Cu  Cu6  1  0.994  0.490  0.496  1.0
  Cu  Cu7  1  0.494  0.980  0.485  1.0
  O  O8  1  0.818  0.297  0.123  1.0
  O  O9  1  0.171  0.693  0.870  1.0
  O  O10  1  0.823  0.693  0.522  1.0
  O  O11  1  0.306  0.473  0.166  1.0
  O  O12  1  0.478  0.163  0.295  1.0
  O  O13  1  0.119  0.809  0.287  1.0
  O  O14  1  0.699  0.861  0.162  1.0
  O  O15  1  0.522  0.809  0.690  1.0
  O  O16  1  0.174  0.297  0.479  1.0
  O  O17  1  0.696  0.507  0.810  1.0
  O  O18  1  0.868  0.163  0.685  1.0
  O  O19  1  0.305  0.114  0.809  1.0
[/CIF]
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