The crystal structure described by Na3CoCAsO7 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(6) atoms. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form distorted NaO7 pentagonal bipyramids that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Na(2)O7 pentagonal bipyramids, corners with two equivalent As(1)O4 tetrahedra,  an edgeedge with one Co(1)O6 octahedra,  an edgeedge with one Na(2)O7 pentagonal bipyramid,  an edgeedge with one As(1)O4 tetrahedra,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Na(2)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 58°. Co(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form distorted CoO6 octahedra that share corners with two equivalent Na(2)O7 pentagonal bipyramids, corners with four equivalent As(1)O4 tetrahedra, edges with two equivalent Na(2)O7 pentagonal bipyramids, and faces with two equivalent Na(2)O7 pentagonal bipyramids. 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(4), one O(5), and two equivalent O(6) atoms to form AsO4 tetrahedra that share corners with four equivalent Co(1)O6 octahedra, corners with four equivalent Na(2)O7 pentagonal bipyramids, and edges with two equivalent Na(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 43-59°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one C(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Co(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted trigonal bipyramidal geometry to one Na(1), two equivalent Na(2), one Co(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Na(2), one Co(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(2), one Co(1), and one As(1) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Co(1), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3CoAsCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.263
_cell_length_b   6.862
_cell_length_c   9.156
_cell_angle_alpha   90.001
_cell_angle_beta   88.932
_cell_angle_gamma   90.006
_symmetry_Int_Tables_number   1
_cell_volume   330.642
_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
  As  As0  1  0.298  0.750  0.583  1.0
  As  As1  1  0.702  0.250  0.417  1.0
  C  C2  1  0.273  0.250  0.941  1.0
  C  C3  1  0.727  0.750  0.059  1.0
  Co  Co4  1  0.217  0.250  0.659  1.0
  Co  Co5  1  0.783  0.750  0.341  1.0
  Na  Na6  1  0.238  0.750  0.919  1.0
  Na  Na7  1  0.762  0.250  0.081  1.0
  Na  Na8  1  0.749  0.996  0.741  1.0
  Na  Na9  1  0.749  0.504  0.741  1.0
  Na  Na10  1  0.251  0.496  0.259  1.0
  Na  Na11  1  0.251  0.004  0.259  1.0
  O  O12  1  0.708  0.750  0.918  1.0
  O  O13  1  0.292  0.250  0.082  1.0
  O  O14  1  0.050  0.250  0.880  1.0
  O  O15  1  0.950  0.750  0.120  1.0
  O  O16  1  0.474  0.250  0.856  1.0
  O  O17  1  0.526  0.750  0.144  1.0
  O  O18  1  0.624  0.750  0.553  1.0
  O  O19  1  0.376  0.250  0.447  1.0
  O  O20  1  0.846  0.250  0.583  1.0
  O  O21  1  0.154  0.750  0.417  1.0
  O  O22  1  0.222  0.947  0.693  1.0
  O  O23  1  0.221  0.553  0.693  1.0
  O  O24  1  0.779  0.447  0.307  1.0
  O  O25  1  0.778  0.053  0.307  1.0
[/CIF]
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The crystal structure described by Na3CoCAsO7 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(6) atoms. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form distorted NaO7 pentagonal bipyramids that share  a cornercorner with one Co(1)O6 octahedra, corners with two equivalent Na(2)O7 pentagonal bipyramids, corners with two equivalent As(1)O4 tetrahedra,  an edgeedge with one Co(1)O6 octahedra,  an edgeedge with one Na(2)O7 pentagonal bipyramid,  an edgeedge with one As(1)O4 tetrahedra,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Na(2)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 58°. Co(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form distorted CoO6 octahedra that share corners with two equivalent Na(2)O7 pentagonal bipyramids, corners with four equivalent As(1)O4 tetrahedra, edges with two equivalent Na(2)O7 pentagonal bipyramids, and faces with two equivalent Na(2)O7 pentagonal bipyramids. 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(4), one O(5), and two equivalent O(6) atoms to form AsO4 tetrahedra that share corners with four equivalent Co(1)O6 octahedra, corners with four equivalent Na(2)O7 pentagonal bipyramids, and edges with two equivalent Na(2)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 43-59°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one C(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Co(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted trigonal bipyramidal geometry to one Na(1), two equivalent Na(2), one Co(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Na(2), one Co(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(2), one Co(1), and one As(1) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), one Co(1), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3CoAsCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.263
_cell_length_b   6.862
_cell_length_c   9.156
_cell_angle_alpha   90.001
_cell_angle_beta   88.932
_cell_angle_gamma   90.006
_symmetry_Int_Tables_number   1
_cell_volume   330.642
_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
  As  As0  1  0.298  0.750  0.583  1.0
  As  As1  1  0.702  0.250  0.417  1.0
  C  C2  1  0.273  0.250  0.941  1.0
  C  C3  1  0.727  0.750  0.059  1.0
  Co  Co4  1  0.217  0.250  0.659  1.0
  Co  Co5  1  0.783  0.750  0.341  1.0
  Na  Na6  1  0.238  0.750  0.919  1.0
  Na  Na7  1  0.762  0.250  0.081  1.0
  Na  Na8  1  0.749  0.996  0.741  1.0
  Na  Na9  1  0.749  0.504  0.741  1.0
  Na  Na10  1  0.251  0.496  0.259  1.0
  Na  Na11  1  0.251  0.004  0.259  1.0
  O  O12  1  0.708  0.750  0.918  1.0
  O  O13  1  0.292  0.250  0.082  1.0
  O  O14  1  0.050  0.250  0.880  1.0
  O  O15  1  0.950  0.750  0.120  1.0
  O  O16  1  0.474  0.250  0.856  1.0
  O  O17  1  0.526  0.750  0.144  1.0
  O  O18  1  0.624  0.750  0.553  1.0
  O  O19  1  0.376  0.250  0.447  1.0
  O  O20  1  0.846  0.250  0.583  1.0
  O  O21  1  0.154  0.750  0.417  1.0
  O  O22  1  0.222  0.947  0.693  1.0
  O  O23  1  0.221  0.553  0.693  1.0
  O  O24  1  0.779  0.447  0.307  1.0
  O  O25  1  0.778  0.053  0.307  1.0
[/CIF]
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