The structure described by Na3SiCBiO7 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(4) atoms. In the second Na site, Na(2) 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. Si(1) is bonded in a tetrahedral geometry to one O(5), one O(6), and two equivalent O(4) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. Bi(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), two equivalent Na(2), and one C(1) atom to form distorted ONa4C trigonal bipyramids that share corners with two equivalent O(1)Na4C trigonal bipyramids and  an edgeedge with one O(5)Na2SiBi tetrahedra. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Na(2), one C(1), and one Bi(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Na(2), one C(1), and one Bi(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Si(1), and one Bi(1) atom. In the fifth O site, O(5) is bonded to two equivalent Na(2), one Si(1), and one Bi(1) atom to form distorted edge-sharing ONa2SiBi tetrahedra. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(2), one Si(1), and one Bi(1) atom. is represented by the CIF file [CIF]
data_Na3SiBiCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.192
_cell_length_b   5.243
_cell_length_c   9.474
_cell_angle_alpha   89.297
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   357.220
_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  0.250  0.769  0.913  1.0
  Na  Na1  1  0.012  0.246  0.747  1.0
  Na  Na2  1  0.488  0.246  0.747  1.0
  Na  Na3  1  0.512  0.754  0.253  1.0
  Na  Na4  1  0.988  0.754  0.253  1.0
  Na  Na5  1  0.750  0.231  0.087  1.0
  Si  Si6  1  0.250  0.709  0.595  1.0
  Si  Si7  1  0.750  0.291  0.405  1.0
  Bi  Bi8  1  0.750  0.771  0.633  1.0
  Bi  Bi9  1  0.250  0.229  0.367  1.0
  C  C10  1  0.750  0.731  0.948  1.0
  C  C11  1  0.250  0.269  0.052  1.0
  O  O12  1  0.250  0.279  0.916  1.0
  O  O13  1  0.750  0.952  0.882  1.0
  O  O14  1  0.750  0.520  0.875  1.0
  O  O15  1  0.068  0.805  0.685  1.0
  O  O16  1  0.432  0.805  0.685  1.0
  O  O17  1  0.250  0.393  0.590  1.0
  O  O18  1  0.750  0.190  0.573  1.0
  O  O19  1  0.250  0.810  0.427  1.0
  O  O20  1  0.750  0.607  0.410  1.0
  O  O21  1  0.568  0.195  0.315  1.0
  O  O22  1  0.932  0.195  0.315  1.0
  O  O23  1  0.250  0.480  0.125  1.0
  O  O24  1  0.250  0.048  0.118  1.0
  O  O25  1  0.750  0.721  0.084  1.0
[/CIF]
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The structure described by Na3SiCBiO7 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(4) atoms. In the second Na site, Na(2) 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. Si(1) is bonded in a tetrahedral geometry to one O(5), one O(6), and two equivalent O(4) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. Bi(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), two equivalent Na(2), and one C(1) atom to form distorted ONa4C trigonal bipyramids that share corners with two equivalent O(1)Na4C trigonal bipyramids and  an edgeedge with one O(5)Na2SiBi tetrahedra. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Na(2), one C(1), and one Bi(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Na(2), one C(1), and one Bi(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Si(1), and one Bi(1) atom. In the fifth O site, O(5) is bonded to two equivalent Na(2), one Si(1), and one Bi(1) atom to form distorted edge-sharing ONa2SiBi tetrahedra. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(2), one Si(1), and one Bi(1) atom. is represented by the CIF file [CIF]
data_Na3SiBiCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.192
_cell_length_b   5.243
_cell_length_c   9.474
_cell_angle_alpha   89.297
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   357.220
_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  0.250  0.769  0.913  1.0
  Na  Na1  1  0.012  0.246  0.747  1.0
  Na  Na2  1  0.488  0.246  0.747  1.0
  Na  Na3  1  0.512  0.754  0.253  1.0
  Na  Na4  1  0.988  0.754  0.253  1.0
  Na  Na5  1  0.750  0.231  0.087  1.0
  Si  Si6  1  0.250  0.709  0.595  1.0
  Si  Si7  1  0.750  0.291  0.405  1.0
  Bi  Bi8  1  0.750  0.771  0.633  1.0
  Bi  Bi9  1  0.250  0.229  0.367  1.0
  C  C10  1  0.750  0.731  0.948  1.0
  C  C11  1  0.250  0.269  0.052  1.0
  O  O12  1  0.250  0.279  0.916  1.0
  O  O13  1  0.750  0.952  0.882  1.0
  O  O14  1  0.750  0.520  0.875  1.0
  O  O15  1  0.068  0.805  0.685  1.0
  O  O16  1  0.432  0.805  0.685  1.0
  O  O17  1  0.250  0.393  0.590  1.0
  O  O18  1  0.750  0.190  0.573  1.0
  O  O19  1  0.250  0.810  0.427  1.0
  O  O20  1  0.750  0.607  0.410  1.0
  O  O21  1  0.568  0.195  0.315  1.0
  O  O22  1  0.932  0.195  0.315  1.0
  O  O23  1  0.250  0.480  0.125  1.0
  O  O24  1  0.250  0.048  0.118  1.0
  O  O25  1  0.750  0.721  0.084  1.0
[/CIF]
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