The structure described by YCuO3 crystallizes in the hexagonal P6_3cm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one O(1), three equivalent O(3), and three equivalent O(4) atoms. In the second Y site, Y(2) is bonded in a 7-coordinate geometry to one O(2), three equivalent O(3), and three equivalent O(4) atoms. Cu(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form corner-sharing CuO5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Y(1) and three equivalent Cu(1) atoms to form distorted OYCu3 trigonal pyramids that share corners with six equivalent O(3)Y3Cu tetrahedra, corners with three equivalent O(1)YCu3 trigonal pyramids, corners with three equivalent O(2)YCu3 trigonal pyramids, and edges with three equivalent O(4)Y3Cu tetrahedra. In the second O site, O(2) is bonded to one Y(2) and three equivalent Cu(1) atoms to form OYCu3 trigonal pyramids that share corners with six equivalent O(4)Y3Cu tetrahedra, corners with six equivalent O(1)YCu3 trigonal pyramids, and edges with three equivalent O(3)Y3Cu tetrahedra. In the third O site, O(3) is bonded to one Y(2), two equivalent Y(1), and one Cu(1) atom to form OY3Cu tetrahedra that share corners with four equivalent O(4)Y3Cu tetrahedra, corners with six equivalent O(3)Y3Cu tetrahedra, corners with four equivalent O(1)YCu3 trigonal pyramids, edges with three equivalent O(4)Y3Cu tetrahedra, and  an edgeedge with one O(2)YCu3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Y(2), two equivalent Y(1), and one Cu(1) atom to form OY3Cu tetrahedra that share corners with four equivalent O(3)Y3Cu tetrahedra, corners with six equivalent O(4)Y3Cu tetrahedra, corners with two equivalent O(2)YCu3 trigonal pyramids, edges with three equivalent O(3)Y3Cu tetrahedra, and edges with two equivalent O(1)YCu3 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_YCuO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.182
_cell_length_b   6.182
_cell_length_c   11.030
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.998
_symmetry_Int_Tables_number   1
_cell_volume   365.101
_cell_formula_units_Z   6
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
  Y  Y0  1  0.667  0.333  0.236  1.0
  Y  Y1  1  0.333  0.667  0.736  1.0
  Y  Y2  1  0.667  0.333  0.736  1.0
  Y  Y3  1  0.333  0.667  0.236  1.0
  Y  Y4  1  1.000  1.000  0.774  1.0
  Y  Y5  1  1.000  1.000  0.274  1.0
  Cu  Cu6  1  0.667  1.000  0.501  1.0
  Cu  Cu7  1  0.667  0.667  0.001  1.0
  Cu  Cu8  1  0.000  0.333  0.001  1.0
  Cu  Cu9  1  1.000  0.667  0.501  1.0
  Cu  Cu10  1  0.333  0.333  0.501  1.0
  Cu  Cu11  1  0.333  0.000  0.001  1.0
  O  O12  1  0.667  0.333  0.015  1.0
  O  O13  1  0.333  0.667  0.515  1.0
  O  O14  1  0.667  0.333  0.515  1.0
  O  O15  1  0.333  0.667  0.015  1.0
  O  O16  1  1.000  1.000  0.985  1.0
  O  O17  1  0.000  1.000  0.485  1.0
  O  O18  1  0.353  0.000  0.838  1.0
  O  O19  1  0.353  0.353  0.338  1.0
  O  O20  1  1.000  0.647  0.338  1.0
  O  O21  1  0.000  0.353  0.838  1.0
  O  O22  1  0.647  0.647  0.838  1.0
  O  O23  1  0.647  1.000  0.338  1.0
  O  O24  1  0.313  0.000  0.165  1.0
  O  O25  1  0.313  0.313  0.665  1.0
  O  O26  1  1.000  0.687  0.665  1.0
  O  O27  1  0.000  0.313  0.165  1.0
  O  O28  1  0.687  0.687  0.165  1.0
  O  O29  1  0.687  1.000  0.665  1.0
[/CIF]
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The structure described by YCuO3 crystallizes in the hexagonal P6_3cm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 7-coordinate geometry to one O(1), three equivalent O(3), and three equivalent O(4) atoms. In the second Y site, Y(2) is bonded in a 7-coordinate geometry to one O(2), three equivalent O(3), and three equivalent O(4) atoms. Cu(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form corner-sharing CuO5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Y(1) and three equivalent Cu(1) atoms to form distorted OYCu3 trigonal pyramids that share corners with six equivalent O(3)Y3Cu tetrahedra, corners with three equivalent O(1)YCu3 trigonal pyramids, corners with three equivalent O(2)YCu3 trigonal pyramids, and edges with three equivalent O(4)Y3Cu tetrahedra. In the second O site, O(2) is bonded to one Y(2) and three equivalent Cu(1) atoms to form OYCu3 trigonal pyramids that share corners with six equivalent O(4)Y3Cu tetrahedra, corners with six equivalent O(1)YCu3 trigonal pyramids, and edges with three equivalent O(3)Y3Cu tetrahedra. In the third O site, O(3) is bonded to one Y(2), two equivalent Y(1), and one Cu(1) atom to form OY3Cu tetrahedra that share corners with four equivalent O(4)Y3Cu tetrahedra, corners with six equivalent O(3)Y3Cu tetrahedra, corners with four equivalent O(1)YCu3 trigonal pyramids, edges with three equivalent O(4)Y3Cu tetrahedra, and  an edgeedge with one O(2)YCu3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Y(2), two equivalent Y(1), and one Cu(1) atom to form OY3Cu tetrahedra that share corners with four equivalent O(3)Y3Cu tetrahedra, corners with six equivalent O(4)Y3Cu tetrahedra, corners with two equivalent O(2)YCu3 trigonal pyramids, edges with three equivalent O(3)Y3Cu tetrahedra, and edges with two equivalent O(1)YCu3 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_YCuO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.182
_cell_length_b   6.182
_cell_length_c   11.030
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.998
_symmetry_Int_Tables_number   1
_cell_volume   365.101
_cell_formula_units_Z   6
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
  Y  Y0  1  0.667  0.333  0.236  1.0
  Y  Y1  1  0.333  0.667  0.736  1.0
  Y  Y2  1  0.667  0.333  0.736  1.0
  Y  Y3  1  0.333  0.667  0.236  1.0
  Y  Y4  1  1.000  1.000  0.774  1.0
  Y  Y5  1  1.000  1.000  0.274  1.0
  Cu  Cu6  1  0.667  1.000  0.501  1.0
  Cu  Cu7  1  0.667  0.667  0.001  1.0
  Cu  Cu8  1  0.000  0.333  0.001  1.0
  Cu  Cu9  1  1.000  0.667  0.501  1.0
  Cu  Cu10  1  0.333  0.333  0.501  1.0
  Cu  Cu11  1  0.333  0.000  0.001  1.0
  O  O12  1  0.667  0.333  0.015  1.0
  O  O13  1  0.333  0.667  0.515  1.0
  O  O14  1  0.667  0.333  0.515  1.0
  O  O15  1  0.333  0.667  0.015  1.0
  O  O16  1  1.000  1.000  0.985  1.0
  O  O17  1  0.000  1.000  0.485  1.0
  O  O18  1  0.353  0.000  0.838  1.0
  O  O19  1  0.353  0.353  0.338  1.0
  O  O20  1  1.000  0.647  0.338  1.0
  O  O21  1  0.000  0.353  0.838  1.0
  O  O22  1  0.647  0.647  0.838  1.0
  O  O23  1  0.647  1.000  0.338  1.0
  O  O24  1  0.313  0.000  0.165  1.0
  O  O25  1  0.313  0.313  0.665  1.0
  O  O26  1  1.000  0.687  0.665  1.0
  O  O27  1  0.000  0.313  0.165  1.0
  O  O28  1  0.687  0.687  0.165  1.0
  O  O29  1  0.687  1.000  0.665  1.0
[/CIF]
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