The crystal structure described by Na2Ge2O5 crystallizes in the orthorhombic Pna2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(4) atoms to form distorted NaO5 square pyramids that share corners with four equivalent Na(1)O5 square pyramids, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, and  an edgeedge with one Ge(1)O4 tetrahedra. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(3), one O(5), two equivalent O(1), and two equivalent O(4) atoms. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(5), and two equivalent O(2) atoms to form GeO4 tetrahedra that share corners with two equivalent Na(1)O5 square pyramids,  a cornercorner with one Ge(2)O4 tetrahedra, corners with two equivalent Ge(1)O4 tetrahedra, and  an edgeedge with one Na(1)O5 square pyramid. In the second Ge site, Ge(2) is bonded to one O(4), one O(5), and two equivalent O(3) atoms to form GeO4 tetrahedra that share corners with two equivalent Na(1)O5 square pyramids,  a cornercorner with one Ge(1)O4 tetrahedra, and corners with two equivalent Ge(2)O4 tetrahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), two equivalent Na(2), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing ONa4Ge trigonal bipyramids. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(1) and two equivalent Ge(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Na(2) and two equivalent Ge(2) atoms. In the fourth O site, O(4) is bonded to two equivalent Na(1), two equivalent Na(2), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing ONa4Ge trigonal bipyramids. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Na(2), one Ge(1), and one Ge(2) atom. is represented by the CIF file [CIF]
data_Na2Ge2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.883
_cell_length_b   8.438
_cell_length_c   12.104
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   498.656
_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  0.432  0.927  0.767  1.0
  Na  Na1  1  0.397  0.814  0.305  1.0
  Na  Na2  1  0.897  0.686  0.805  1.0
  Na  Na3  1  0.932  0.573  0.267  1.0
  Na  Na4  1  0.432  0.427  0.733  1.0
  Na  Na5  1  0.397  0.314  0.195  1.0
  Na  Na6  1  0.897  0.186  0.695  1.0
  Na  Na7  1  0.932  0.073  0.233  1.0
  Ge  Ge8  1  0.486  0.951  0.073  1.0
  Ge  Ge9  1  0.850  0.889  0.475  1.0
  Ge  Ge10  1  0.350  0.611  0.975  1.0
  Ge  Ge11  1  0.986  0.549  0.573  1.0
  Ge  Ge12  1  0.486  0.451  0.427  1.0
  Ge  Ge13  1  0.850  0.389  0.025  1.0
  Ge  Ge14  1  0.350  0.111  0.525  1.0
  Ge  Ge15  1  0.986  0.049  0.927  1.0
  O  O16  1  0.911  0.959  0.805  1.0
  O  O17  1  0.846  0.972  0.051  1.0
  O  O18  1  0.490  0.926  0.484  1.0
  O  O19  1  0.920  0.833  0.342  1.0
  O  O20  1  0.919  0.755  0.584  1.0
  O  O21  1  0.419  0.745  0.084  1.0
  O  O22  1  0.420  0.667  0.842  1.0
  O  O23  1  0.990  0.574  0.984  1.0
  O  O24  1  0.346  0.528  0.551  1.0
  O  O25  1  0.411  0.541  0.305  1.0
  O  O26  1  0.911  0.459  0.695  1.0
  O  O27  1  0.846  0.472  0.449  1.0
  O  O28  1  0.490  0.426  0.016  1.0
  O  O29  1  0.920  0.333  0.158  1.0
  O  O30  1  0.919  0.255  0.916  1.0
  O  O31  1  0.419  0.245  0.416  1.0
  O  O32  1  0.420  0.167  0.658  1.0
  O  O33  1  0.990  0.074  0.516  1.0
  O  O34  1  0.346  0.028  0.949  1.0
  O  O35  1  0.411  0.041  0.195  1.0
[/CIF]
.
The crystal structure described by Na2Ge2O5 crystallizes in the orthorhombic Pna2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(4) atoms to form distorted NaO5 square pyramids that share corners with four equivalent Na(1)O5 square pyramids, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 tetrahedra, and  an edgeedge with one Ge(1)O4 tetrahedra. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(3), one O(5), two equivalent O(1), and two equivalent O(4) atoms. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(5), and two equivalent O(2) atoms to form GeO4 tetrahedra that share corners with two equivalent Na(1)O5 square pyramids,  a cornercorner with one Ge(2)O4 tetrahedra, corners with two equivalent Ge(1)O4 tetrahedra, and  an edgeedge with one Na(1)O5 square pyramid. In the second Ge site, Ge(2) is bonded to one O(4), one O(5), and two equivalent O(3) atoms to form GeO4 tetrahedra that share corners with two equivalent Na(1)O5 square pyramids,  a cornercorner with one Ge(1)O4 tetrahedra, and corners with two equivalent Ge(2)O4 tetrahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), two equivalent Na(2), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing ONa4Ge trigonal bipyramids. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(1) and two equivalent Ge(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Na(2) and two equivalent Ge(2) atoms. In the fourth O site, O(4) is bonded to two equivalent Na(1), two equivalent Na(2), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing ONa4Ge trigonal bipyramids. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Na(2), one Ge(1), and one Ge(2) atom. is represented by the CIF file [CIF]
data_Na2Ge2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.883
_cell_length_b   8.438
_cell_length_c   12.104
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   498.656
_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  0.432  0.927  0.767  1.0
  Na  Na1  1  0.397  0.814  0.305  1.0
  Na  Na2  1  0.897  0.686  0.805  1.0
  Na  Na3  1  0.932  0.573  0.267  1.0
  Na  Na4  1  0.432  0.427  0.733  1.0
  Na  Na5  1  0.397  0.314  0.195  1.0
  Na  Na6  1  0.897  0.186  0.695  1.0
  Na  Na7  1  0.932  0.073  0.233  1.0
  Ge  Ge8  1  0.486  0.951  0.073  1.0
  Ge  Ge9  1  0.850  0.889  0.475  1.0
  Ge  Ge10  1  0.350  0.611  0.975  1.0
  Ge  Ge11  1  0.986  0.549  0.573  1.0
  Ge  Ge12  1  0.486  0.451  0.427  1.0
  Ge  Ge13  1  0.850  0.389  0.025  1.0
  Ge  Ge14  1  0.350  0.111  0.525  1.0
  Ge  Ge15  1  0.986  0.049  0.927  1.0
  O  O16  1  0.911  0.959  0.805  1.0
  O  O17  1  0.846  0.972  0.051  1.0
  O  O18  1  0.490  0.926  0.484  1.0
  O  O19  1  0.920  0.833  0.342  1.0
  O  O20  1  0.919  0.755  0.584  1.0
  O  O21  1  0.419  0.745  0.084  1.0
  O  O22  1  0.420  0.667  0.842  1.0
  O  O23  1  0.990  0.574  0.984  1.0
  O  O24  1  0.346  0.528  0.551  1.0
  O  O25  1  0.411  0.541  0.305  1.0
  O  O26  1  0.911  0.459  0.695  1.0
  O  O27  1  0.846  0.472  0.449  1.0
  O  O28  1  0.490  0.426  0.016  1.0
  O  O29  1  0.920  0.333  0.158  1.0
  O  O30  1  0.919  0.255  0.916  1.0
  O  O31  1  0.419  0.245  0.416  1.0
  O  O32  1  0.420  0.167  0.658  1.0
  O  O33  1  0.990  0.074  0.516  1.0
  O  O34  1  0.346  0.028  0.949  1.0
  O  O35  1  0.411  0.041  0.195  1.0
[/CIF]
.