The crystal structure described by Na2SiCBiO7 crystallizes in the monoclinic P2_1/m space group. Na(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted NaO6 octahedra that share corners with two equivalent Bi(1)O6 octahedra, corners with three equivalent Si(1)O4 tetrahedra,  an edgeedge with one Na(1)O6 octahedra,  a faceface with one Na(1)O6 octahedra, and  a faceface with one Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 63-81°. Si(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with four equivalent Bi(1)O6 octahedra and corners with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-69°. 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 to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted BiO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, corners with four equivalent Si(1)O4 tetrahedra, and faces with two equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 63-81°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Na(1) and one C(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one C(1), and one Bi(1) atom. In the third O site, O(3) is bonded to two equivalent Na(1), one C(1), and one Bi(1) atom to form distorted corner-sharing ONa2BiC trigonal pyramids. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Si(1), and one Bi(1) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Si(1), and one Bi(1) atom. In the sixth O site, O(6) is bonded to two equivalent Na(1), one Si(1), and one Bi(1) atom to form distorted corner-sharing ONa2SiBi tetrahedra. is represented by the CIF file [CIF]
data_Na2SiBiCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.956
_cell_length_b   5.358
_cell_length_c   9.312
_cell_angle_alpha   88.823
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   346.943
_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  0.007  0.231  0.779  1.0
  Na  Na1  1  0.493  0.231  0.779  1.0
  Na  Na2  1  0.507  0.769  0.221  1.0
  Na  Na3  1  0.993  0.769  0.221  1.0
  Si  Si4  1  0.250  0.710  0.584  1.0
  Si  Si5  1  0.750  0.290  0.416  1.0
  Bi  Bi6  1  0.750  0.785  0.634  1.0
  Bi  Bi7  1  0.250  0.215  0.366  1.0
  C  C8  1  0.750  0.728  0.932  1.0
  C  C9  1  0.250  0.272  0.068  1.0
  O  O10  1  0.250  0.296  0.934  1.0
  O  O11  1  0.750  0.948  0.865  1.0
  O  O12  1  0.750  0.531  0.847  1.0
  O  O13  1  0.065  0.825  0.670  1.0
  O  O14  1  0.435  0.825  0.670  1.0
  O  O15  1  0.750  0.198  0.588  1.0
  O  O16  1  0.250  0.401  0.588  1.0
  O  O17  1  0.750  0.599  0.412  1.0
  O  O18  1  0.250  0.802  0.412  1.0
  O  O19  1  0.565  0.175  0.330  1.0
  O  O20  1  0.935  0.175  0.330  1.0
  O  O21  1  0.250  0.469  0.153  1.0
  O  O22  1  0.250  0.052  0.135  1.0
  O  O23  1  0.750  0.704  0.066  1.0
[/CIF]
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The crystal structure described by Na2SiCBiO7 crystallizes in the monoclinic P2_1/m space group. Na(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted NaO6 octahedra that share corners with two equivalent Bi(1)O6 octahedra, corners with three equivalent Si(1)O4 tetrahedra,  an edgeedge with one Na(1)O6 octahedra,  a faceface with one Na(1)O6 octahedra, and  a faceface with one Bi(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 63-81°. Si(1) is bonded to one O(5), one O(6), and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with four equivalent Bi(1)O6 octahedra and corners with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-69°. 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 to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form distorted BiO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, corners with four equivalent Si(1)O4 tetrahedra, and faces with two equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 63-81°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Na(1) and one C(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one C(1), and one Bi(1) atom. In the third O site, O(3) is bonded to two equivalent Na(1), one C(1), and one Bi(1) atom to form distorted corner-sharing ONa2BiC trigonal pyramids. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Si(1), and one Bi(1) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Si(1), and one Bi(1) atom. In the sixth O site, O(6) is bonded to two equivalent Na(1), one Si(1), and one Bi(1) atom to form distorted corner-sharing ONa2SiBi tetrahedra. is represented by the CIF file [CIF]
data_Na2SiBiCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.956
_cell_length_b   5.358
_cell_length_c   9.312
_cell_angle_alpha   88.823
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   346.943
_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  0.007  0.231  0.779  1.0
  Na  Na1  1  0.493  0.231  0.779  1.0
  Na  Na2  1  0.507  0.769  0.221  1.0
  Na  Na3  1  0.993  0.769  0.221  1.0
  Si  Si4  1  0.250  0.710  0.584  1.0
  Si  Si5  1  0.750  0.290  0.416  1.0
  Bi  Bi6  1  0.750  0.785  0.634  1.0
  Bi  Bi7  1  0.250  0.215  0.366  1.0
  C  C8  1  0.750  0.728  0.932  1.0
  C  C9  1  0.250  0.272  0.068  1.0
  O  O10  1  0.250  0.296  0.934  1.0
  O  O11  1  0.750  0.948  0.865  1.0
  O  O12  1  0.750  0.531  0.847  1.0
  O  O13  1  0.065  0.825  0.670  1.0
  O  O14  1  0.435  0.825  0.670  1.0
  O  O15  1  0.750  0.198  0.588  1.0
  O  O16  1  0.250  0.401  0.588  1.0
  O  O17  1  0.750  0.599  0.412  1.0
  O  O18  1  0.250  0.802  0.412  1.0
  O  O19  1  0.565  0.175  0.330  1.0
  O  O20  1  0.935  0.175  0.330  1.0
  O  O21  1  0.250  0.469  0.153  1.0
  O  O22  1  0.250  0.052  0.135  1.0
  O  O23  1  0.750  0.704  0.066  1.0
[/CIF]
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