The crystal structure described by Ca2TaNiO6 is Orthorhombic Perovskite-derived structured and crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(3), one O(4), two equivalent O(2), and four equivalent O(1) atoms. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(3), one O(4), two equivalent O(1), and four equivalent O(2) atoms. Ta(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra and corners with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-30°. Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra and corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-32°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Ca(2), two equivalent Ca(1), one Ta(1), and one Ni(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ca(1), two equivalent Ca(2), one Ta(1), and one Ni(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), and two equivalent Ni(1) atoms to form distorted corner-sharing OCa2Ni2 tetrahedra. is represented by the CIF card [CIF]
data_Ca2TaNiO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.457
_cell_length_b   5.633
_cell_length_c   7.729
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   88.329
_symmetry_Int_Tables_number   1
_cell_volume   237.492
_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
  Ca  Ca0  1  0.024  0.957  0.250  1.0
  Ca  Ca1  1  0.491  0.433  0.250  1.0
  Ca  Ca2  1  0.509  0.567  0.750  1.0
  Ca  Ca3  1  0.976  0.043  0.750  1.0
  Ta  Ta4  1  0.000  0.500  0.000  1.0
  Ta  Ta5  1  0.000  0.500  0.500  1.0
  Ni  Ni6  1  0.500  0.000  0.000  1.0
  Ni  Ni7  1  0.500  0.000  0.500  1.0
  O  O8  1  0.796  0.792  0.547  1.0
  O  O9  1  0.288  0.698  0.456  1.0
  O  O10  1  0.204  0.208  0.453  1.0
  O  O11  1  0.712  0.302  0.956  1.0
  O  O12  1  0.090  0.474  0.750  1.0
  O  O13  1  0.712  0.302  0.544  1.0
  O  O14  1  0.288  0.698  0.044  1.0
  O  O15  1  0.796  0.792  0.953  1.0
  O  O16  1  0.596  0.026  0.250  1.0
  O  O17  1  0.204  0.208  0.047  1.0
  O  O18  1  0.404  0.974  0.750  1.0
  O  O19  1  0.910  0.526  0.250  1.0
[/CIF]
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The crystal structure described by Ca2TaNiO6 is Orthorhombic Perovskite-derived structured and crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(3), one O(4), two equivalent O(2), and four equivalent O(1) atoms. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(3), one O(4), two equivalent O(1), and four equivalent O(2) atoms. Ta(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra and corners with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-30°. Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra and corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-32°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Ca(2), two equivalent Ca(1), one Ta(1), and one Ni(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ca(1), two equivalent Ca(2), one Ta(1), and one Ni(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), and two equivalent Ta(1) atoms. In the fourth O site, O(4) is bonded to one Ca(1), one Ca(2), and two equivalent Ni(1) atoms to form distorted corner-sharing OCa2Ni2 tetrahedra. is represented by the CIF card [CIF]
data_Ca2TaNiO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.457
_cell_length_b   5.633
_cell_length_c   7.729
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   88.329
_symmetry_Int_Tables_number   1
_cell_volume   237.492
_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
  Ca  Ca0  1  0.024  0.957  0.250  1.0
  Ca  Ca1  1  0.491  0.433  0.250  1.0
  Ca  Ca2  1  0.509  0.567  0.750  1.0
  Ca  Ca3  1  0.976  0.043  0.750  1.0
  Ta  Ta4  1  0.000  0.500  0.000  1.0
  Ta  Ta5  1  0.000  0.500  0.500  1.0
  Ni  Ni6  1  0.500  0.000  0.000  1.0
  Ni  Ni7  1  0.500  0.000  0.500  1.0
  O  O8  1  0.796  0.792  0.547  1.0
  O  O9  1  0.288  0.698  0.456  1.0
  O  O10  1  0.204  0.208  0.453  1.0
  O  O11  1  0.712  0.302  0.956  1.0
  O  O12  1  0.090  0.474  0.750  1.0
  O  O13  1  0.712  0.302  0.544  1.0
  O  O14  1  0.288  0.698  0.044  1.0
  O  O15  1  0.796  0.792  0.953  1.0
  O  O16  1  0.596  0.026  0.250  1.0
  O  O17  1  0.204  0.208  0.047  1.0
  O  O18  1  0.404  0.974  0.750  1.0
  O  O19  1  0.910  0.526  0.250  1.0
[/CIF]
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