The material structure described by CaEu(NiO3)4 crystallizes in the tetragonal P4/mmm space group. Ca(1) is bonded to four equivalent O(3) and eight equivalent O(1) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, corners with eight equivalent Eu(1)O12 cuboctahedra, and faces with eight equivalent Ni(1)O6 octahedra. Eu(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form EuO12 cuboctahedra that share corners with four equivalent Eu(1)O12 cuboctahedra, corners with eight equivalent Ca(1)O12 cuboctahedra, and faces with eight equivalent Ni(1)O6 octahedra. Ni(1) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, faces with two equivalent Ca(1)O12 cuboctahedra, and faces with two equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted square co-planar geometry to one Ca(1), one Eu(1), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent Eu(1) and two equivalent Ni(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Ca(1) and two equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_CaEu(NiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.170
_cell_length_b   5.170
_cell_length_c   7.161
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   191.380
_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
  Ca  Ca0  1  0.500  0.500  0.000  1.0
  Eu  Eu1  1  0.000  0.000  0.500  1.0
  Ni  Ni2  1  0.000  0.500  0.750  1.0
  Ni  Ni3  1  0.000  0.500  0.250  1.0
  Ni  Ni4  1  0.500  0.000  0.750  1.0
  Ni  Ni5  1  0.500  0.000  0.250  1.0
  O  O6  1  0.249  0.249  0.750  1.0
  O  O7  1  0.249  0.249  0.250  1.0
  O  O8  1  0.751  0.751  0.750  1.0
  O  O9  1  0.751  0.751  0.250  1.0
  O  O10  1  0.751  0.249  0.750  1.0
  O  O11  1  0.751  0.249  0.250  1.0
  O  O12  1  0.249  0.751  0.250  1.0
  O  O13  1  0.249  0.751  0.750  1.0
  O  O14  1  0.000  0.500  0.500  1.0
  O  O15  1  0.000  0.500  0.000  1.0
  O  O16  1  0.500  0.000  0.500  1.0
  O  O17  1  0.500  0.000  0.000  1.0
[/CIF]
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The material structure described by CaEu(NiO3)4 crystallizes in the tetragonal P4/mmm space group. Ca(1) is bonded to four equivalent O(3) and eight equivalent O(1) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, corners with eight equivalent Eu(1)O12 cuboctahedra, and faces with eight equivalent Ni(1)O6 octahedra. Eu(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form EuO12 cuboctahedra that share corners with four equivalent Eu(1)O12 cuboctahedra, corners with eight equivalent Ca(1)O12 cuboctahedra, and faces with eight equivalent Ni(1)O6 octahedra. Ni(1) is bonded to one O(2), one O(3), and four equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, faces with two equivalent Ca(1)O12 cuboctahedra, and faces with two equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted square co-planar geometry to one Ca(1), one Eu(1), and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent Eu(1) and two equivalent Ni(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Ca(1) and two equivalent Ni(1) atoms. is represented by the CIF file [CIF]
data_CaEu(NiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.170
_cell_length_b   5.170
_cell_length_c   7.161
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   191.380
_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
  Ca  Ca0  1  0.500  0.500  0.000  1.0
  Eu  Eu1  1  0.000  0.000  0.500  1.0
  Ni  Ni2  1  0.000  0.500  0.750  1.0
  Ni  Ni3  1  0.000  0.500  0.250  1.0
  Ni  Ni4  1  0.500  0.000  0.750  1.0
  Ni  Ni5  1  0.500  0.000  0.250  1.0
  O  O6  1  0.249  0.249  0.750  1.0
  O  O7  1  0.249  0.249  0.250  1.0
  O  O8  1  0.751  0.751  0.750  1.0
  O  O9  1  0.751  0.751  0.250  1.0
  O  O10  1  0.751  0.249  0.750  1.0
  O  O11  1  0.751  0.249  0.250  1.0
  O  O12  1  0.249  0.751  0.250  1.0
  O  O13  1  0.249  0.751  0.750  1.0
  O  O14  1  0.000  0.500  0.500  1.0
  O  O15  1  0.000  0.500  0.000  1.0
  O  O16  1  0.500  0.000  0.500  1.0
  O  O17  1  0.500  0.000  0.000  1.0
[/CIF]
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