The compound described by Cu2TiO3 crystallizes in the monoclinic C2/c space group. Ti(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form a mixture of distorted corner and edge-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 29°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a linear geometry to one O(1) and one O(2) atom. In the second Cu site, Cu(2) is bonded in a distorted trigonal planar geometry to one O(3) and two equivalent O(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ti(1), one Cu(1), and two equivalent Cu(2) atoms to form distorted OTiCu3 trigonal pyramids that share corners with three equivalent O(3)Ti2Cu2 tetrahedra, corners with two equivalent O(4)Ti4 trigonal pyramids, and corners with two equivalent O(1)TiCu3 trigonal pyramids. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Ti(1) and one Cu(1) atom. In the third O site, O(3) is bonded to two equivalent Ti(1) and two equivalent Cu(2) atoms to form OTi2Cu2 tetrahedra that share corners with two equivalent O(4)Ti4 trigonal pyramids, corners with six equivalent O(1)TiCu3 trigonal pyramids, and  an edgeedge with one O(4)Ti4 trigonal pyramid. In the fourth O site, O(4) is bonded to four equivalent Ti(1) atoms to form distorted OTi4 trigonal pyramids that share corners with two equivalent O(3)Ti2Cu2 tetrahedra, corners with four equivalent O(1)TiCu3 trigonal pyramids,  an edgeedge with one O(3)Ti2Cu2 tetrahedra, and edges with two equivalent O(4)Ti4 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_TiCu2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.781
_cell_length_b   8.781
_cell_length_c   4.969
_cell_angle_alpha   78.335
_cell_angle_beta   78.335
_cell_angle_gamma   49.655
_symmetry_Int_Tables_number   1
_cell_volume   284.684
_cell_formula_units_Z   4
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
  Ti  Ti0  1  0.448  0.715  0.978  1.0
  Ti  Ti1  1  0.715  0.448  0.478  1.0
  Ti  Ti2  1  0.285  0.552  0.522  1.0
  Ti  Ti3  1  0.552  0.285  0.022  1.0
  Cu  Cu4  1  0.881  0.636  0.739  1.0
  Cu  Cu5  1  0.636  0.881  0.239  1.0
  Cu  Cu6  1  0.002  0.184  0.904  1.0
  Cu  Cu7  1  0.184  0.002  0.404  1.0
  Cu  Cu8  1  0.816  0.998  0.596  1.0
  Cu  Cu9  1  0.998  0.816  0.096  1.0
  Cu  Cu10  1  0.364  0.119  0.761  1.0
  Cu  Cu11  1  0.119  0.364  0.261  1.0
  O  O12  1  0.297  0.960  0.756  1.0
  O  O13  1  0.573  0.718  0.244  1.0
  O  O14  1  0.960  0.297  0.256  1.0
  O  O15  1  0.718  0.573  0.744  1.0
  O  O16  1  0.211  0.789  0.250  1.0
  O  O17  1  0.566  0.434  0.250  1.0
  O  O18  1  0.789  0.211  0.750  1.0
  O  O19  1  0.434  0.566  0.750  1.0
  O  O20  1  0.282  0.427  0.256  1.0
  O  O21  1  0.040  0.703  0.744  1.0
  O  O22  1  0.427  0.282  0.756  1.0
  O  O23  1  0.703  0.040  0.244  1.0
[/CIF]
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The compound described by Cu2TiO3 crystallizes in the monoclinic C2/c space group. Ti(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form a mixture of distorted corner and edge-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 29°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a linear geometry to one O(1) and one O(2) atom. In the second Cu site, Cu(2) is bonded in a distorted trigonal planar geometry to one O(3) and two equivalent O(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ti(1), one Cu(1), and two equivalent Cu(2) atoms to form distorted OTiCu3 trigonal pyramids that share corners with three equivalent O(3)Ti2Cu2 tetrahedra, corners with two equivalent O(4)Ti4 trigonal pyramids, and corners with two equivalent O(1)TiCu3 trigonal pyramids. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Ti(1) and one Cu(1) atom. In the third O site, O(3) is bonded to two equivalent Ti(1) and two equivalent Cu(2) atoms to form OTi2Cu2 tetrahedra that share corners with two equivalent O(4)Ti4 trigonal pyramids, corners with six equivalent O(1)TiCu3 trigonal pyramids, and  an edgeedge with one O(4)Ti4 trigonal pyramid. In the fourth O site, O(4) is bonded to four equivalent Ti(1) atoms to form distorted OTi4 trigonal pyramids that share corners with two equivalent O(3)Ti2Cu2 tetrahedra, corners with four equivalent O(1)TiCu3 trigonal pyramids,  an edgeedge with one O(3)Ti2Cu2 tetrahedra, and edges with two equivalent O(4)Ti4 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_TiCu2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.781
_cell_length_b   8.781
_cell_length_c   4.969
_cell_angle_alpha   78.335
_cell_angle_beta   78.335
_cell_angle_gamma   49.655
_symmetry_Int_Tables_number   1
_cell_volume   284.684
_cell_formula_units_Z   4
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
  Ti  Ti0  1  0.448  0.715  0.978  1.0
  Ti  Ti1  1  0.715  0.448  0.478  1.0
  Ti  Ti2  1  0.285  0.552  0.522  1.0
  Ti  Ti3  1  0.552  0.285  0.022  1.0
  Cu  Cu4  1  0.881  0.636  0.739  1.0
  Cu  Cu5  1  0.636  0.881  0.239  1.0
  Cu  Cu6  1  0.002  0.184  0.904  1.0
  Cu  Cu7  1  0.184  0.002  0.404  1.0
  Cu  Cu8  1  0.816  0.998  0.596  1.0
  Cu  Cu9  1  0.998  0.816  0.096  1.0
  Cu  Cu10  1  0.364  0.119  0.761  1.0
  Cu  Cu11  1  0.119  0.364  0.261  1.0
  O  O12  1  0.297  0.960  0.756  1.0
  O  O13  1  0.573  0.718  0.244  1.0
  O  O14  1  0.960  0.297  0.256  1.0
  O  O15  1  0.718  0.573  0.744  1.0
  O  O16  1  0.211  0.789  0.250  1.0
  O  O17  1  0.566  0.434  0.250  1.0
  O  O18  1  0.789  0.211  0.750  1.0
  O  O19  1  0.434  0.566  0.750  1.0
  O  O20  1  0.282  0.427  0.256  1.0
  O  O21  1  0.040  0.703  0.744  1.0
  O  O22  1  0.427  0.282  0.756  1.0
  O  O23  1  0.703  0.040  0.244  1.0
[/CIF]
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