The compound described by SrTiCuO4 crystallizes in the tetragonal P4/nmm space group. Sr(1) is bonded in a 9-coordinate geometry to four equivalent O(3) and five equivalent O(1) atoms. Ti(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form TiO6 octahedra that share corners with four equivalent Ti(1)O6 octahedra and edges with four equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles are 4°. Cu(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form distorted CuO6 octahedra that share corners with four equivalent Cu(1)O6 octahedra, edges with four equivalent Ti(1)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles are 17°. There are three inequivalent O sites. In the first O site, O(1) is bonded to five equivalent Sr(1) and one Ti(1) atom to form distorted OSr5Ti octahedra that share corners with four equivalent O(1)Sr5Ti octahedra,  a cornercorner with one O(2)TiCu4 square pyramid, corners with twelve equivalent O(3)Sr2Ti2Cu trigonal bipyramids, edges with eight equivalent O(1)Sr5Ti octahedra, and faces with four equivalent O(3)Sr2Ti2Cu trigonal bipyramids. The corner-sharing octahedral tilt angles are 12°. In the second O site, O(2) is bonded to one Ti(1) and four equivalent Cu(1) atoms to form OTiCu4 square pyramids that share  a cornercorner with one O(1)Sr5Ti octahedra, corners with four equivalent O(2)TiCu4 square pyramids, corners with four equivalent O(3)Sr2Ti2Cu trigonal bipyramids, edges with four equivalent O(2)TiCu4 square pyramids, and edges with four equivalent O(3)Sr2Ti2Cu trigonal bipyramids. The corner-sharing octahedra are not tilted. In the third O site, O(3) is bonded to two equivalent Sr(1), two equivalent Ti(1), and one Cu(1) atom to form distorted OSr2Ti2Cu trigonal bipyramids that share corners with six equivalent O(1)Sr5Ti octahedra, corners with two equivalent O(2)TiCu4 square pyramids, corners with five equivalent O(3)Sr2Ti2Cu trigonal bipyramids, edges with two equivalent O(2)TiCu4 square pyramids, edges with four equivalent O(3)Sr2Ti2Cu trigonal bipyramids, and faces with two equivalent O(1)Sr5Ti octahedra. The corner-sharing octahedral tilt angles range from 50-53°. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrTiCuO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.955
_cell_length_b   3.955
_cell_length_c   11.093
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   173.495
_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
  Sr  Sr0  1  0.750  0.750  0.127  1.0
  Sr  Sr1  1  0.250  0.250  0.873  1.0
  Ti  Ti2  1  0.750  0.750  0.729  1.0
  Ti  Ti3  1  0.250  0.250  0.271  1.0
  Cu  Cu4  1  0.250  0.750  0.500  1.0
  Cu  Cu5  1  0.750  0.250  0.500  1.0
  O  O6  1  0.750  0.750  0.899  1.0
  O  O7  1  0.250  0.250  0.101  1.0
  O  O8  1  0.750  0.750  0.526  1.0
  O  O9  1  0.250  0.250  0.474  1.0
  O  O10  1  0.750  0.250  0.722  1.0
  O  O11  1  0.250  0.750  0.722  1.0
  O  O12  1  0.250  0.750  0.278  1.0
  O  O13  1  0.750  0.250  0.278  1.0
[/CIF]
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The compound described by SrTiCuO4 crystallizes in the tetragonal P4/nmm space group. Sr(1) is bonded in a 9-coordinate geometry to four equivalent O(3) and five equivalent O(1) atoms. Ti(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form TiO6 octahedra that share corners with four equivalent Ti(1)O6 octahedra and edges with four equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles are 4°. Cu(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form distorted CuO6 octahedra that share corners with four equivalent Cu(1)O6 octahedra, edges with four equivalent Ti(1)O6 octahedra, and edges with four equivalent Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles are 17°. There are three inequivalent O sites. In the first O site, O(1) is bonded to five equivalent Sr(1) and one Ti(1) atom to form distorted OSr5Ti octahedra that share corners with four equivalent O(1)Sr5Ti octahedra,  a cornercorner with one O(2)TiCu4 square pyramid, corners with twelve equivalent O(3)Sr2Ti2Cu trigonal bipyramids, edges with eight equivalent O(1)Sr5Ti octahedra, and faces with four equivalent O(3)Sr2Ti2Cu trigonal bipyramids. The corner-sharing octahedral tilt angles are 12°. In the second O site, O(2) is bonded to one Ti(1) and four equivalent Cu(1) atoms to form OTiCu4 square pyramids that share  a cornercorner with one O(1)Sr5Ti octahedra, corners with four equivalent O(2)TiCu4 square pyramids, corners with four equivalent O(3)Sr2Ti2Cu trigonal bipyramids, edges with four equivalent O(2)TiCu4 square pyramids, and edges with four equivalent O(3)Sr2Ti2Cu trigonal bipyramids. The corner-sharing octahedra are not tilted. In the third O site, O(3) is bonded to two equivalent Sr(1), two equivalent Ti(1), and one Cu(1) atom to form distorted OSr2Ti2Cu trigonal bipyramids that share corners with six equivalent O(1)Sr5Ti octahedra, corners with two equivalent O(2)TiCu4 square pyramids, corners with five equivalent O(3)Sr2Ti2Cu trigonal bipyramids, edges with two equivalent O(2)TiCu4 square pyramids, edges with four equivalent O(3)Sr2Ti2Cu trigonal bipyramids, and faces with two equivalent O(1)Sr5Ti octahedra. The corner-sharing octahedral tilt angles range from 50-53°. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrTiCuO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.955
_cell_length_b   3.955
_cell_length_c   11.093
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   173.495
_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
  Sr  Sr0  1  0.750  0.750  0.127  1.0
  Sr  Sr1  1  0.250  0.250  0.873  1.0
  Ti  Ti2  1  0.750  0.750  0.729  1.0
  Ti  Ti3  1  0.250  0.250  0.271  1.0
  Cu  Cu4  1  0.250  0.750  0.500  1.0
  Cu  Cu5  1  0.750  0.250  0.500  1.0
  O  O6  1  0.750  0.750  0.899  1.0
  O  O7  1  0.250  0.250  0.101  1.0
  O  O8  1  0.750  0.750  0.526  1.0
  O  O9  1  0.250  0.250  0.474  1.0
  O  O10  1  0.750  0.250  0.722  1.0
  O  O11  1  0.250  0.750  0.722  1.0
  O  O12  1  0.250  0.750  0.278  1.0
  O  O13  1  0.750  0.250  0.278  1.0
[/CIF]
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