The structure described by Na6NiO4 is alpha Pu-derived structured and crystallizes in the monoclinic Cc space group. There are six inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to one O(3), one O(4), and two equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. In the third Na site, Na(3) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Na(3)O4 trigonal pyramids, corners with four equivalent Na(6)O4 trigonal pyramids, and  an edgeedge with one Ni(1)O4 tetrahedra. In the fourth Na site, Na(4) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), and two equivalent O(4) atoms. In the fifth Na site, Na(5) is bonded in a 3-coordinate geometry to one O(1), one O(2), one O(3), and two equivalent O(4) atoms. In the sixth Na site, Na(6) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Na(3)O4 trigonal pyramids, and  an edgeedge with one Ni(1)O4 tetrahedra. Ni(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form NiO4 tetrahedra that share corners with two equivalent Na(3)O4 trigonal pyramids, corners with two equivalent Na(6)O4 trigonal pyramids,  an edgeedge with one Na(3)O4 trigonal pyramid, and  an edgeedge with one Na(6)O4 trigonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 8-coordinate geometry to one Na(4), one Na(5), one Na(6), two equivalent Na(1), two equivalent Na(2), and one Ni(1) atom. In the second O site, O(2) is bonded in a 8-coordinate geometry to one Na(4), one Na(5), one Na(6), two equivalent Na(2), two equivalent Na(3), and one Ni(1) atom. In the third O site, O(3) is bonded in a 7-coordinate geometry to one Na(1), one Na(2), one Na(3), one Na(4), one Na(5), one Na(6), and one Ni(1) atom. In the fourth O site, O(4) is bonded in a 8-coordinate geometry to one Na(1), one Na(3), one Na(6), two equivalent Na(4), two equivalent Na(5), and one Ni(1) atom. is represented by the CIF file [CIF]
data_Na6NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.516
_cell_length_b   7.492
_cell_length_c   5.782
_cell_angle_alpha   89.927
_cell_angle_beta   90.037
_cell_angle_gamma   119.894
_symmetry_Int_Tables_number   1
_cell_volume   282.287
_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
  Na  Na0  1  0.143  0.859  0.966  1.0
  Na  Na1  1  0.074  0.534  0.638  1.0
  Na  Na2  1  0.143  0.283  0.965  1.0
  Na  Na3  1  0.470  0.937  0.638  1.0
  Na  Na4  1  0.462  0.536  0.629  1.0
  Na  Na5  1  0.288  0.143  0.467  1.0
  Na  Na6  1  0.712  0.855  0.967  1.0
  Na  Na7  1  0.530  0.467  0.138  1.0
  Na  Na8  1  0.538  0.074  0.129  1.0
  Na  Na9  1  0.857  0.716  0.466  1.0
  Na  Na10  1  0.926  0.460  0.138  1.0
  Na  Na11  1  0.857  0.140  0.465  1.0
  Ni  Ni12  1  0.329  0.671  0.249  1.0
  Ni  Ni13  1  0.671  0.342  0.749  1.0
  O  O14  1  0.184  0.811  0.359  1.0
  O  O15  1  0.191  0.377  0.353  1.0
  O  O16  1  0.337  0.663  0.908  1.0
  O  O17  1  0.620  0.805  0.353  1.0
  O  O18  1  0.380  0.185  0.853  1.0
  O  O19  1  0.816  0.627  0.859  1.0
  O  O20  1  0.663  0.326  0.408  1.0
  O  O21  1  0.809  0.187  0.853  1.0
[/CIF]
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The structure described by Na6NiO4 is alpha Pu-derived structured and crystallizes in the monoclinic Cc space group. There are six inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to one O(3), one O(4), and two equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. In the third Na site, Na(3) is bonded to one O(3), one O(4), and two equivalent O(2) atoms to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Na(3)O4 trigonal pyramids, corners with four equivalent Na(6)O4 trigonal pyramids, and  an edgeedge with one Ni(1)O4 tetrahedra. In the fourth Na site, Na(4) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), and two equivalent O(4) atoms. In the fifth Na site, Na(5) is bonded in a 3-coordinate geometry to one O(1), one O(2), one O(3), and two equivalent O(4) atoms. In the sixth Na site, Na(6) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Na(3)O4 trigonal pyramids, and  an edgeedge with one Ni(1)O4 tetrahedra. Ni(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form NiO4 tetrahedra that share corners with two equivalent Na(3)O4 trigonal pyramids, corners with two equivalent Na(6)O4 trigonal pyramids,  an edgeedge with one Na(3)O4 trigonal pyramid, and  an edgeedge with one Na(6)O4 trigonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 8-coordinate geometry to one Na(4), one Na(5), one Na(6), two equivalent Na(1), two equivalent Na(2), and one Ni(1) atom. In the second O site, O(2) is bonded in a 8-coordinate geometry to one Na(4), one Na(5), one Na(6), two equivalent Na(2), two equivalent Na(3), and one Ni(1) atom. In the third O site, O(3) is bonded in a 7-coordinate geometry to one Na(1), one Na(2), one Na(3), one Na(4), one Na(5), one Na(6), and one Ni(1) atom. In the fourth O site, O(4) is bonded in a 8-coordinate geometry to one Na(1), one Na(3), one Na(6), two equivalent Na(4), two equivalent Na(5), and one Ni(1) atom. is represented by the CIF file [CIF]
data_Na6NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.516
_cell_length_b   7.492
_cell_length_c   5.782
_cell_angle_alpha   89.927
_cell_angle_beta   90.037
_cell_angle_gamma   119.894
_symmetry_Int_Tables_number   1
_cell_volume   282.287
_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
  Na  Na0  1  0.143  0.859  0.966  1.0
  Na  Na1  1  0.074  0.534  0.638  1.0
  Na  Na2  1  0.143  0.283  0.965  1.0
  Na  Na3  1  0.470  0.937  0.638  1.0
  Na  Na4  1  0.462  0.536  0.629  1.0
  Na  Na5  1  0.288  0.143  0.467  1.0
  Na  Na6  1  0.712  0.855  0.967  1.0
  Na  Na7  1  0.530  0.467  0.138  1.0
  Na  Na8  1  0.538  0.074  0.129  1.0
  Na  Na9  1  0.857  0.716  0.466  1.0
  Na  Na10  1  0.926  0.460  0.138  1.0
  Na  Na11  1  0.857  0.140  0.465  1.0
  Ni  Ni12  1  0.329  0.671  0.249  1.0
  Ni  Ni13  1  0.671  0.342  0.749  1.0
  O  O14  1  0.184  0.811  0.359  1.0
  O  O15  1  0.191  0.377  0.353  1.0
  O  O16  1  0.337  0.663  0.908  1.0
  O  O17  1  0.620  0.805  0.353  1.0
  O  O18  1  0.380  0.185  0.853  1.0
  O  O19  1  0.816  0.627  0.859  1.0
  O  O20  1  0.663  0.326  0.408  1.0
  O  O21  1  0.809  0.187  0.853  1.0
[/CIF]
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