The crystal structure described by Na2Sn3O7 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to one O(3), one O(5), two equivalent O(2), two equivalent O(4), and two equivalent O(7) atoms. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to two equivalent O(3), two equivalent O(6), and three equivalent O(1) atoms. There are three inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to one O(6), two equivalent O(5), and three equivalent O(7) atoms to form a mixture of corner and edge-sharing SnO6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. In the second Sn site, Sn(2) is bonded to one O(2), one O(5), two equivalent O(3), and two equivalent O(4) atoms to form a mixture of corner and edge-sharing SnO6 octahedra. The corner-sharing octahedral tilt angles are 52°. In the third Sn site, Sn(3) is bonded to one O(4), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of corner and edge-sharing SnO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are seven inequivalent O sites. In the first O site, O(4) is bonded to two equivalent Na(1), one Sn(3), and two equivalent Sn(2) atoms to form distorted ONa2Sn3 trigonal bipyramids that share corners with two equivalent O(2)Na2Sn3 square pyramids, corners with two equivalent O(1)Na3Sn2 square pyramids,  a cornercorner with one O(6)Na2Sn2 tetrahedra, edges with three equivalent O(2)Na2Sn3 square pyramids, and edges with two equivalent O(4)Na2Sn3 trigonal bipyramids. In the second O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one Sn(2), and two equivalent Sn(1) atoms. In the third O site, O(6) is bonded to two equivalent Na(2), one Sn(1), and one Sn(3) atom to form distorted ONa2Sn2 tetrahedra that share corners with two equivalent O(2)Na2Sn3 square pyramids, corners with two equivalent O(1)Na3Sn2 square pyramids, corners with two equivalent O(6)Na2Sn2 tetrahedra,  a cornercorner with one O(4)Na2Sn3 trigonal bipyramid, and edges with three equivalent O(1)Na3Sn2 square pyramids. In the fourth O site, O(7) is bonded in a 5-coordinate geometry to two equivalent Na(1) and three equivalent Sn(1) atoms. In the fifth O site, O(1) is bonded to three equivalent Na(2) and two equivalent Sn(3) atoms to form ONa3Sn2 square pyramids that share corners with two equivalent O(2)Na2Sn3 square pyramids, corners with two equivalent O(6)Na2Sn2 tetrahedra, corners with two equivalent O(4)Na2Sn3 trigonal bipyramids,  an edgeedge with one O(2)Na2Sn3 square pyramid, edges with four equivalent O(1)Na3Sn2 square pyramids, and edges with three equivalent O(6)Na2Sn2 tetrahedra. In the sixth O site, O(2) is bonded to two equivalent Na(1), one Sn(2), and two equivalent Sn(3) atoms to form distorted ONa2Sn3 square pyramids that share corners with two equivalent O(1)Na3Sn2 square pyramids, corners with two equivalent O(6)Na2Sn2 tetrahedra, corners with two equivalent O(4)Na2Sn3 trigonal bipyramids,  an edgeedge with one O(1)Na3Sn2 square pyramid, edges with two equivalent O(2)Na2Sn3 square pyramids, and edges with three equivalent O(4)Na2Sn3 trigonal bipyramids. In the seventh O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), and two equivalent Sn(2) atoms. is represented by the CIF file [CIF]
data_Na2Sn3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.745
_cell_length_b   3.167
_cell_length_c   12.077
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   640.388
_cell_formula_units_Z   4
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  0.307  0.250  0.438  1.0
  Na  Na1  1  0.693  0.750  0.562  1.0
  Na  Na2  1  0.193  0.750  0.938  1.0
  Na  Na3  1  0.807  0.250  0.062  1.0
  Na  Na4  1  0.435  0.250  0.890  1.0
  Na  Na5  1  0.565  0.750  0.110  1.0
  Na  Na6  1  0.065  0.750  0.390  1.0
  Na  Na7  1  0.935  0.250  0.610  1.0
  Sn  Sn8  1  0.022  0.250  0.116  1.0
  Sn  Sn9  1  0.978  0.750  0.884  1.0
  Sn  Sn10  1  0.478  0.750  0.616  1.0
  Sn  Sn11  1  0.522  0.250  0.384  1.0
  Sn  Sn12  1  0.286  0.250  0.710  1.0
  Sn  Sn13  1  0.714  0.750  0.290  1.0
  Sn  Sn14  1  0.214  0.750  0.210  1.0
  Sn  Sn15  1  0.786  0.250  0.790  1.0
  Sn  Sn16  1  0.382  0.250  0.150  1.0
  Sn  Sn17  1  0.618  0.750  0.850  1.0
  Sn  Sn18  1  0.118  0.750  0.650  1.0
  Sn  Sn19  1  0.882  0.250  0.350  1.0
  O  O20  1  0.088  0.250  0.548  1.0
  O  O21  1  0.912  0.750  0.452  1.0
  O  O22  1  0.412  0.750  0.048  1.0
  O  O23  1  0.588  0.250  0.952  1.0
  O  O24  1  0.164  0.250  0.756  1.0
  O  O25  1  0.836  0.750  0.244  1.0
  O  O26  1  0.336  0.750  0.256  1.0
  O  O27  1  0.664  0.250  0.744  1.0
  O  O28  1  0.187  0.250  0.314  1.0
  O  O29  1  0.813  0.750  0.686  1.0
  O  O30  1  0.313  0.750  0.814  1.0
  O  O31  1  0.687  0.250  0.186  1.0
  O  O32  1  0.254  0.250  0.099  1.0
  O  O33  1  0.746  0.750  0.901  1.0
  O  O34  1  0.246  0.750  0.599  1.0
  O  O35  1  0.754  0.250  0.401  1.0
  O  O36  1  0.396  0.250  0.629  1.0
  O  O37  1  0.604  0.750  0.371  1.0
  O  O38  1  0.104  0.750  0.129  1.0
  O  O39  1  0.896  0.250  0.871  1.0
  O  O40  1  0.492  0.250  0.224  1.0
  O  O41  1  0.508  0.750  0.776  1.0
  O  O42  1  0.008  0.750  0.724  1.0
  O  O43  1  0.992  0.250  0.276  1.0
  O  O44  1  0.553  0.250  0.559  1.0
  O  O45  1  0.447  0.750  0.441  1.0
  O  O46  1  0.947  0.750  0.059  1.0
  O  O47  1  0.053  0.250  0.941  1.0
[/CIF]
.
The crystal structure described by Na2Sn3O7 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to one O(3), one O(5), two equivalent O(2), two equivalent O(4), and two equivalent O(7) atoms. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to two equivalent O(3), two equivalent O(6), and three equivalent O(1) atoms. There are three inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to one O(6), two equivalent O(5), and three equivalent O(7) atoms to form a mixture of corner and edge-sharing SnO6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. In the second Sn site, Sn(2) is bonded to one O(2), one O(5), two equivalent O(3), and two equivalent O(4) atoms to form a mixture of corner and edge-sharing SnO6 octahedra. The corner-sharing octahedral tilt angles are 52°. In the third Sn site, Sn(3) is bonded to one O(4), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of corner and edge-sharing SnO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are seven inequivalent O sites. In the first O site, O(4) is bonded to two equivalent Na(1), one Sn(3), and two equivalent Sn(2) atoms to form distorted ONa2Sn3 trigonal bipyramids that share corners with two equivalent O(2)Na2Sn3 square pyramids, corners with two equivalent O(1)Na3Sn2 square pyramids,  a cornercorner with one O(6)Na2Sn2 tetrahedra, edges with three equivalent O(2)Na2Sn3 square pyramids, and edges with two equivalent O(4)Na2Sn3 trigonal bipyramids. In the second O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one Sn(2), and two equivalent Sn(1) atoms. In the third O site, O(6) is bonded to two equivalent Na(2), one Sn(1), and one Sn(3) atom to form distorted ONa2Sn2 tetrahedra that share corners with two equivalent O(2)Na2Sn3 square pyramids, corners with two equivalent O(1)Na3Sn2 square pyramids, corners with two equivalent O(6)Na2Sn2 tetrahedra,  a cornercorner with one O(4)Na2Sn3 trigonal bipyramid, and edges with three equivalent O(1)Na3Sn2 square pyramids. In the fourth O site, O(7) is bonded in a 5-coordinate geometry to two equivalent Na(1) and three equivalent Sn(1) atoms. In the fifth O site, O(1) is bonded to three equivalent Na(2) and two equivalent Sn(3) atoms to form ONa3Sn2 square pyramids that share corners with two equivalent O(2)Na2Sn3 square pyramids, corners with two equivalent O(6)Na2Sn2 tetrahedra, corners with two equivalent O(4)Na2Sn3 trigonal bipyramids,  an edgeedge with one O(2)Na2Sn3 square pyramid, edges with four equivalent O(1)Na3Sn2 square pyramids, and edges with three equivalent O(6)Na2Sn2 tetrahedra. In the sixth O site, O(2) is bonded to two equivalent Na(1), one Sn(2), and two equivalent Sn(3) atoms to form distorted ONa2Sn3 square pyramids that share corners with two equivalent O(1)Na3Sn2 square pyramids, corners with two equivalent O(6)Na2Sn2 tetrahedra, corners with two equivalent O(4)Na2Sn3 trigonal bipyramids,  an edgeedge with one O(1)Na3Sn2 square pyramid, edges with two equivalent O(2)Na2Sn3 square pyramids, and edges with three equivalent O(4)Na2Sn3 trigonal bipyramids. In the seventh O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Na(2), and two equivalent Sn(2) atoms. is represented by the CIF file [CIF]
data_Na2Sn3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.745
_cell_length_b   3.167
_cell_length_c   12.077
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   640.388
_cell_formula_units_Z   4
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  0.307  0.250  0.438  1.0
  Na  Na1  1  0.693  0.750  0.562  1.0
  Na  Na2  1  0.193  0.750  0.938  1.0
  Na  Na3  1  0.807  0.250  0.062  1.0
  Na  Na4  1  0.435  0.250  0.890  1.0
  Na  Na5  1  0.565  0.750  0.110  1.0
  Na  Na6  1  0.065  0.750  0.390  1.0
  Na  Na7  1  0.935  0.250  0.610  1.0
  Sn  Sn8  1  0.022  0.250  0.116  1.0
  Sn  Sn9  1  0.978  0.750  0.884  1.0
  Sn  Sn10  1  0.478  0.750  0.616  1.0
  Sn  Sn11  1  0.522  0.250  0.384  1.0
  Sn  Sn12  1  0.286  0.250  0.710  1.0
  Sn  Sn13  1  0.714  0.750  0.290  1.0
  Sn  Sn14  1  0.214  0.750  0.210  1.0
  Sn  Sn15  1  0.786  0.250  0.790  1.0
  Sn  Sn16  1  0.382  0.250  0.150  1.0
  Sn  Sn17  1  0.618  0.750  0.850  1.0
  Sn  Sn18  1  0.118  0.750  0.650  1.0
  Sn  Sn19  1  0.882  0.250  0.350  1.0
  O  O20  1  0.088  0.250  0.548  1.0
  O  O21  1  0.912  0.750  0.452  1.0
  O  O22  1  0.412  0.750  0.048  1.0
  O  O23  1  0.588  0.250  0.952  1.0
  O  O24  1  0.164  0.250  0.756  1.0
  O  O25  1  0.836  0.750  0.244  1.0
  O  O26  1  0.336  0.750  0.256  1.0
  O  O27  1  0.664  0.250  0.744  1.0
  O  O28  1  0.187  0.250  0.314  1.0
  O  O29  1  0.813  0.750  0.686  1.0
  O  O30  1  0.313  0.750  0.814  1.0
  O  O31  1  0.687  0.250  0.186  1.0
  O  O32  1  0.254  0.250  0.099  1.0
  O  O33  1  0.746  0.750  0.901  1.0
  O  O34  1  0.246  0.750  0.599  1.0
  O  O35  1  0.754  0.250  0.401  1.0
  O  O36  1  0.396  0.250  0.629  1.0
  O  O37  1  0.604  0.750  0.371  1.0
  O  O38  1  0.104  0.750  0.129  1.0
  O  O39  1  0.896  0.250  0.871  1.0
  O  O40  1  0.492  0.250  0.224  1.0
  O  O41  1  0.508  0.750  0.776  1.0
  O  O42  1  0.008  0.750  0.724  1.0
  O  O43  1  0.992  0.250  0.276  1.0
  O  O44  1  0.553  0.250  0.559  1.0
  O  O45  1  0.447  0.750  0.441  1.0
  O  O46  1  0.947  0.750  0.059  1.0
  O  O47  1  0.053  0.250  0.941  1.0
[/CIF]
.