The crystal structure described by Na2NiCAsO7 crystallizes in the monoclinic P2_1/m space group. Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. Ni(1) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted NiO6 octahedra that share corners with four equivalent As(1)O4 tetrahedra. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. As(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form AsO4 tetrahedra that share corners with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-57°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one C(1) atom. In the second O site, O(2) is bonded in a distorted trigonal pyramidal geometry to two equivalent Na(1), one Ni(1), and one C(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ni(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and one As(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent Na(1), one Ni(1), and one As(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ni(1), and one As(1) atom. is represented by the CIF file [CIF]
data_Na2NiAsCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.712
_cell_length_b   5.281
_cell_length_c   9.117
_cell_angle_alpha   87.575
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   322.881
_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  0.505  0.767  0.767  1.0
  Na  Na1  1  0.995  0.767  0.767  1.0
  Na  Na2  1  0.495  0.233  0.233  1.0
  Na  Na3  1  0.005  0.233  0.233  1.0
  Ni  Ni4  1  0.250  0.214  0.653  1.0
  Ni  Ni5  1  0.750  0.786  0.347  1.0
  As  As6  1  0.750  0.290  0.573  1.0
  As  As7  1  0.250  0.710  0.427  1.0
  C  C8  1  0.250  0.281  0.922  1.0
  C  C9  1  0.750  0.719  0.078  1.0
  O  O10  1  0.750  0.713  0.940  1.0
  O  O11  1  0.250  0.063  0.858  1.0
  O  O12  1  0.250  0.477  0.833  1.0
  O  O13  1  0.950  0.209  0.682  1.0
  O  O14  1  0.550  0.209  0.682  1.0
  O  O15  1  0.250  0.846  0.594  1.0
  O  O16  1  0.750  0.621  0.544  1.0
  O  O17  1  0.250  0.379  0.456  1.0
  O  O18  1  0.750  0.154  0.406  1.0
  O  O19  1  0.450  0.791  0.318  1.0
  O  O20  1  0.050  0.791  0.318  1.0
  O  O21  1  0.750  0.523  0.167  1.0
  O  O22  1  0.750  0.937  0.142  1.0
  O  O23  1  0.250  0.287  0.060  1.0
[/CIF]
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The crystal structure described by Na2NiCAsO7 crystallizes in the monoclinic P2_1/m space group. Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. Ni(1) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted NiO6 octahedra that share corners with four equivalent As(1)O4 tetrahedra. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. As(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form AsO4 tetrahedra that share corners with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-57°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one C(1) atom. In the second O site, O(2) is bonded in a distorted trigonal pyramidal geometry to two equivalent Na(1), one Ni(1), and one C(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ni(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and one As(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent Na(1), one Ni(1), and one As(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ni(1), and one As(1) atom. is represented by the CIF file [CIF]
data_Na2NiAsCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.712
_cell_length_b   5.281
_cell_length_c   9.117
_cell_angle_alpha   87.575
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   322.881
_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  0.505  0.767  0.767  1.0
  Na  Na1  1  0.995  0.767  0.767  1.0
  Na  Na2  1  0.495  0.233  0.233  1.0
  Na  Na3  1  0.005  0.233  0.233  1.0
  Ni  Ni4  1  0.250  0.214  0.653  1.0
  Ni  Ni5  1  0.750  0.786  0.347  1.0
  As  As6  1  0.750  0.290  0.573  1.0
  As  As7  1  0.250  0.710  0.427  1.0
  C  C8  1  0.250  0.281  0.922  1.0
  C  C9  1  0.750  0.719  0.078  1.0
  O  O10  1  0.750  0.713  0.940  1.0
  O  O11  1  0.250  0.063  0.858  1.0
  O  O12  1  0.250  0.477  0.833  1.0
  O  O13  1  0.950  0.209  0.682  1.0
  O  O14  1  0.550  0.209  0.682  1.0
  O  O15  1  0.250  0.846  0.594  1.0
  O  O16  1  0.750  0.621  0.544  1.0
  O  O17  1  0.250  0.379  0.456  1.0
  O  O18  1  0.750  0.154  0.406  1.0
  O  O19  1  0.450  0.791  0.318  1.0
  O  O20  1  0.050  0.791  0.318  1.0
  O  O21  1  0.750  0.523  0.167  1.0
  O  O22  1  0.750  0.937  0.142  1.0
  O  O23  1  0.250  0.287  0.060  1.0
[/CIF]
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