The crystal structure described by Rb3NiO2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the monoclinic P2_1 space group. There are six inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a distorted linear geometry to one O(1) and one O(3) atom. In the second Rb site, Rb(2) is bonded in a distorted linear geometry to one O(2) and one O(4) atom. In the third Rb site, Rb(3) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form a mixture of edge and corner-sharing RbO4 tetrahedra. In the fourth Rb site, Rb(4) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form a mixture of distorted edge and corner-sharing RbO4 tetrahedra. In the fifth Rb site, Rb(5) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form a mixture of distorted edge and corner-sharing RbO4 tetrahedra. In the sixth Rb site, Rb(6) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form a mixture of edge and corner-sharing RbO4 tetrahedra. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a linear geometry to one O(2) and one O(4) atom. In the second Ni site, Ni(2) is bonded in a linear geometry to one O(1) and one O(3) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Rb(1), one Rb(5), one Rb(6), two equivalent Rb(3), and one Ni(2) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Rb(2), one Rb(5), one Rb(6), two equivalent Rb(4), and one Ni(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Rb(1), one Rb(5), one Rb(6), two equivalent Rb(3), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Rb(2), one Rb(5), one Rb(6), two equivalent Rb(4), and one Ni(1) atom. is represented by the CIF card [CIF]
data_Rb3NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.339
_cell_length_b   6.339
_cell_length_c   14.901
_cell_angle_alpha   89.959
_cell_angle_beta   90.098
_cell_angle_gamma   90.021
_symmetry_Int_Tables_number   1
_cell_volume   598.812
_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
  Rb  Rb0  1  0.957  0.043  0.750  1.0
  Rb  Rb1  1  0.043  0.957  0.250  1.0
  Rb  Rb2  1  0.543  0.543  0.500  1.0
  Rb  Rb3  1  0.457  0.457  1.000  1.0
  Rb  Rb4  1  0.482  0.021  0.624  1.0
  Rb  Rb5  1  0.518  0.979  0.124  1.0
  Rb  Rb6  1  0.521  0.018  0.374  1.0
  Rb  Rb7  1  0.480  0.981  0.875  1.0
  Rb  Rb8  1  0.980  0.518  0.876  1.0
  Rb  Rb9  1  0.020  0.481  0.375  1.0
  Rb  Rb10  1  0.018  0.520  0.626  1.0
  Rb  Rb11  1  0.982  0.480  0.126  1.0
  Ni  Ni12  1  0.504  0.496  0.250  1.0
  Ni  Ni13  1  0.996  0.997  1.000  1.0
  Ni  Ni14  1  0.496  0.504  0.750  1.0
  Ni  Ni15  1  0.004  0.004  0.500  1.0
  O  O16  1  0.695  0.705  0.740  1.0
  O  O17  1  0.305  0.295  0.241  1.0
  O  O18  1  0.205  0.805  0.491  1.0
  O  O19  1  0.794  0.195  0.990  1.0
  O  O20  1  0.295  0.305  0.759  1.0
  O  O21  1  0.705  0.695  0.260  1.0
  O  O22  1  0.805  0.205  0.510  1.0
  O  O23  1  0.194  0.795  0.009  1.0
[/CIF]
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The crystal structure described by Rb3NiO2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the monoclinic P2_1 space group. There are six inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a distorted linear geometry to one O(1) and one O(3) atom. In the second Rb site, Rb(2) is bonded in a distorted linear geometry to one O(2) and one O(4) atom. In the third Rb site, Rb(3) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form a mixture of edge and corner-sharing RbO4 tetrahedra. In the fourth Rb site, Rb(4) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form a mixture of distorted edge and corner-sharing RbO4 tetrahedra. In the fifth Rb site, Rb(5) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form a mixture of distorted edge and corner-sharing RbO4 tetrahedra. In the sixth Rb site, Rb(6) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form a mixture of edge and corner-sharing RbO4 tetrahedra. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a linear geometry to one O(2) and one O(4) atom. In the second Ni site, Ni(2) is bonded in a linear geometry to one O(1) and one O(3) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Rb(1), one Rb(5), one Rb(6), two equivalent Rb(3), and one Ni(2) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Rb(2), one Rb(5), one Rb(6), two equivalent Rb(4), and one Ni(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Rb(1), one Rb(5), one Rb(6), two equivalent Rb(3), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Rb(2), one Rb(5), one Rb(6), two equivalent Rb(4), and one Ni(1) atom. is represented by the CIF card [CIF]
data_Rb3NiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.339
_cell_length_b   6.339
_cell_length_c   14.901
_cell_angle_alpha   89.959
_cell_angle_beta   90.098
_cell_angle_gamma   90.021
_symmetry_Int_Tables_number   1
_cell_volume   598.812
_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
  Rb  Rb0  1  0.957  0.043  0.750  1.0
  Rb  Rb1  1  0.043  0.957  0.250  1.0
  Rb  Rb2  1  0.543  0.543  0.500  1.0
  Rb  Rb3  1  0.457  0.457  1.000  1.0
  Rb  Rb4  1  0.482  0.021  0.624  1.0
  Rb  Rb5  1  0.518  0.979  0.124  1.0
  Rb  Rb6  1  0.521  0.018  0.374  1.0
  Rb  Rb7  1  0.480  0.981  0.875  1.0
  Rb  Rb8  1  0.980  0.518  0.876  1.0
  Rb  Rb9  1  0.020  0.481  0.375  1.0
  Rb  Rb10  1  0.018  0.520  0.626  1.0
  Rb  Rb11  1  0.982  0.480  0.126  1.0
  Ni  Ni12  1  0.504  0.496  0.250  1.0
  Ni  Ni13  1  0.996  0.997  1.000  1.0
  Ni  Ni14  1  0.496  0.504  0.750  1.0
  Ni  Ni15  1  0.004  0.004  0.500  1.0
  O  O16  1  0.695  0.705  0.740  1.0
  O  O17  1  0.305  0.295  0.241  1.0
  O  O18  1  0.205  0.805  0.491  1.0
  O  O19  1  0.794  0.195  0.990  1.0
  O  O20  1  0.295  0.305  0.759  1.0
  O  O21  1  0.705  0.695  0.260  1.0
  O  O22  1  0.805  0.205  0.510  1.0
  O  O23  1  0.194  0.795  0.009  1.0
[/CIF]
.