The material structure described by Na3MnSiCO7 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 corners with two equivalent Na(2)O7 pentagonal bipyramids, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Na(2)O7 pentagonal bipyramid,  an edgeedge with one Si(1)O4 tetrahedra,  a faceface with one Na(2)O7 pentagonal bipyramid, and  a faceface with one Mn(1)O5 square pyramid. Mn(1) is bonded to one O(2), one O(4), one O(5), and two equivalent O(6) atoms to form distorted MnO5 square pyramids that share corners with four equivalent Na(2)O7 pentagonal bipyramids, corners with four equivalent Si(1)O4 tetrahedra, and faces with two equivalent Na(2)O7 pentagonal bipyramids. Si(1) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form SiO4 tetrahedra that share corners with four equivalent Na(2)O7 pentagonal bipyramids, corners with four equivalent Mn(1)O5 square pyramids, and edges 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. 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 Mn(1), and one C(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Na(1), two equivalent Na(2), 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 Mn(1), and one Si(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent Na(2), one Mn(1), and one Si(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 Mn(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3MnSiCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.307
_cell_length_b   6.504
_cell_length_c   9.134
_cell_angle_alpha   90.000
_cell_angle_beta   91.066
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   315.262
_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
  C  C0  1  0.285  0.750  0.054  1.0
  C  C1  1  0.715  0.250  0.946  1.0
  Mn  Mn2  1  0.218  0.750  0.353  1.0
  Mn  Mn3  1  0.782  0.250  0.647  1.0
  Na  Na4  1  0.216  0.250  0.092  1.0
  Na  Na5  1  0.784  0.750  0.908  1.0
  Na  Na6  1  0.739  0.007  0.266  1.0
  Na  Na7  1  0.739  0.493  0.266  1.0
  Na  Na8  1  0.261  0.507  0.734  1.0
  Na  Na9  1  0.261  0.993  0.734  1.0
  O  O10  1  0.756  0.250  0.086  1.0
  O  O11  1  0.244  0.750  0.914  1.0
  O  O12  1  0.087  0.750  0.140  1.0
  O  O13  1  0.913  0.250  0.860  1.0
  O  O14  1  0.508  0.750  0.111  1.0
  O  O15  1  0.492  0.250  0.889  1.0
  O  O16  1  0.618  0.250  0.459  1.0
  O  O17  1  0.382  0.750  0.541  1.0
  O  O18  1  0.843  0.750  0.420  1.0
  O  O19  1  0.157  0.250  0.580  1.0
  O  O20  1  0.245  0.050  0.320  1.0
  O  O21  1  0.245  0.450  0.320  1.0
  O  O22  1  0.755  0.550  0.680  1.0
  O  O23  1  0.755  0.950  0.680  1.0
  Si  Si24  1  0.307  0.250  0.427  1.0
  Si  Si25  1  0.693  0.750  0.573  1.0
[/CIF]
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The material structure described by Na3MnSiCO7 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 corners with two equivalent Na(2)O7 pentagonal bipyramids, corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Si(1)O4 tetrahedra,  an edgeedge with one Na(2)O7 pentagonal bipyramid,  an edgeedge with one Si(1)O4 tetrahedra,  a faceface with one Na(2)O7 pentagonal bipyramid, and  a faceface with one Mn(1)O5 square pyramid. Mn(1) is bonded to one O(2), one O(4), one O(5), and two equivalent O(6) atoms to form distorted MnO5 square pyramids that share corners with four equivalent Na(2)O7 pentagonal bipyramids, corners with four equivalent Si(1)O4 tetrahedra, and faces with two equivalent Na(2)O7 pentagonal bipyramids. Si(1) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form SiO4 tetrahedra that share corners with four equivalent Na(2)O7 pentagonal bipyramids, corners with four equivalent Mn(1)O5 square pyramids, and edges 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. 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 Mn(1), and one C(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Na(1), two equivalent Na(2), 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 Mn(1), and one Si(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent Na(2), one Mn(1), and one Si(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 Mn(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3MnSiCO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.307
_cell_length_b   6.504
_cell_length_c   9.134
_cell_angle_alpha   90.000
_cell_angle_beta   91.066
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   315.262
_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
  C  C0  1  0.285  0.750  0.054  1.0
  C  C1  1  0.715  0.250  0.946  1.0
  Mn  Mn2  1  0.218  0.750  0.353  1.0
  Mn  Mn3  1  0.782  0.250  0.647  1.0
  Na  Na4  1  0.216  0.250  0.092  1.0
  Na  Na5  1  0.784  0.750  0.908  1.0
  Na  Na6  1  0.739  0.007  0.266  1.0
  Na  Na7  1  0.739  0.493  0.266  1.0
  Na  Na8  1  0.261  0.507  0.734  1.0
  Na  Na9  1  0.261  0.993  0.734  1.0
  O  O10  1  0.756  0.250  0.086  1.0
  O  O11  1  0.244  0.750  0.914  1.0
  O  O12  1  0.087  0.750  0.140  1.0
  O  O13  1  0.913  0.250  0.860  1.0
  O  O14  1  0.508  0.750  0.111  1.0
  O  O15  1  0.492  0.250  0.889  1.0
  O  O16  1  0.618  0.250  0.459  1.0
  O  O17  1  0.382  0.750  0.541  1.0
  O  O18  1  0.843  0.750  0.420  1.0
  O  O19  1  0.157  0.250  0.580  1.0
  O  O20  1  0.245  0.050  0.320  1.0
  O  O21  1  0.245  0.450  0.320  1.0
  O  O22  1  0.755  0.550  0.680  1.0
  O  O23  1  0.755  0.950  0.680  1.0
  Si  Si24  1  0.307  0.250  0.427  1.0
  Si  Si25  1  0.693  0.750  0.573  1.0
[/CIF]
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