The material structure described by Na2GeO9 crystallizes in the monoclinic P2_1 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(1), one O(6), one O(7), one O(9), and two equivalent O(8) atoms. In the second Na site, Na(2) is bonded to one O(2), one O(4), and three equivalent O(3) atoms to form distorted NaO5 trigonal bipyramids that share corners with two equivalent Na(2)O5 trigonal bipyramids, corners with three equivalent Ge(1)O5 trigonal bipyramids,  an edgeedge with one Ge(1)O5 trigonal bipyramid, and edges with two equivalent Na(2)O5 trigonal bipyramids. Ge(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(9) atom to form distorted GeO5 trigonal bipyramids that share corners with three equivalent Na(2)O5 trigonal bipyramids and  an edgeedge with one Na(2)O5 trigonal bipyramid. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Na(1) and one Ge(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(2), one Ge(1), and one O(5) atom. In the third O site, O(3) is bonded to three equivalent Na(2) and one Ge(1) atom to form a mixture of distorted corner and edge-sharing ONa3Ge trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Na(2), one Ge(1), and one O(9) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one O(2) and one O(8) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Na(1) and one O(7) atom. In the seventh O site, O(7) is bonded in a water-like geometry to one Na(1) and one O(6) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to two equivalent Na(1) and one O(5) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Na(1), one Ge(1), and one O(4) atom. is represented by the CIF card [CIF]
data_Na2GeO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.378
_cell_length_b   4.787
_cell_length_c   6.957
_cell_angle_alpha   90.000
_cell_angle_beta   90.813
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   378.906
_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  0.573  0.093  0.814  1.0
  Na  Na1  1  0.427  0.593  0.186  1.0
  Na  Na2  1  0.954  0.327  0.334  1.0
  Na  Na3  1  0.046  0.827  0.666  1.0
  Ge  Ge4  1  0.824  0.385  0.762  1.0
  Ge  Ge5  1  0.176  0.885  0.238  1.0
  O  O6  1  0.692  0.373  0.643  1.0
  O  O7  1  0.308  0.873  0.357  1.0
  O  O8  1  0.816  0.454  0.057  1.0
  O  O9  1  0.184  0.954  0.943  1.0
  O  O10  1  0.962  0.332  0.675  1.0
  O  O11  1  0.038  0.832  0.325  1.0
  O  O12  1  0.859  0.791  0.799  1.0
  O  O13  1  0.141  0.291  0.201  1.0
  O  O14  1  0.719  0.609  0.116  1.0
  O  O15  1  0.281  0.109  0.884  1.0
  O  O16  1  0.482  0.683  0.627  1.0
  O  O17  1  0.518  0.183  0.373  1.0
  O  O18  1  0.587  0.016  0.300  1.0
  O  O19  1  0.413  0.516  0.700  1.0
  O  O20  1  0.617  0.525  0.036  1.0
  O  O21  1  0.383  0.025  0.964  1.0
  O  O22  1  0.777  0.973  0.860  1.0
  O  O23  1  0.223  0.473  0.140  1.0
[/CIF]
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The material structure described by Na2GeO9 crystallizes in the monoclinic P2_1 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(1), one O(6), one O(7), one O(9), and two equivalent O(8) atoms. In the second Na site, Na(2) is bonded to one O(2), one O(4), and three equivalent O(3) atoms to form distorted NaO5 trigonal bipyramids that share corners with two equivalent Na(2)O5 trigonal bipyramids, corners with three equivalent Ge(1)O5 trigonal bipyramids,  an edgeedge with one Ge(1)O5 trigonal bipyramid, and edges with two equivalent Na(2)O5 trigonal bipyramids. Ge(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(9) atom to form distorted GeO5 trigonal bipyramids that share corners with three equivalent Na(2)O5 trigonal bipyramids and  an edgeedge with one Na(2)O5 trigonal bipyramid. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Na(1) and one Ge(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(2), one Ge(1), and one O(5) atom. In the third O site, O(3) is bonded to three equivalent Na(2) and one Ge(1) atom to form a mixture of distorted corner and edge-sharing ONa3Ge trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Na(2), one Ge(1), and one O(9) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one O(2) and one O(8) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Na(1) and one O(7) atom. In the seventh O site, O(7) is bonded in a water-like geometry to one Na(1) and one O(6) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to two equivalent Na(1) and one O(5) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Na(1), one Ge(1), and one O(4) atom. is represented by the CIF card [CIF]
data_Na2GeO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.378
_cell_length_b   4.787
_cell_length_c   6.957
_cell_angle_alpha   90.000
_cell_angle_beta   90.813
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   378.906
_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  0.573  0.093  0.814  1.0
  Na  Na1  1  0.427  0.593  0.186  1.0
  Na  Na2  1  0.954  0.327  0.334  1.0
  Na  Na3  1  0.046  0.827  0.666  1.0
  Ge  Ge4  1  0.824  0.385  0.762  1.0
  Ge  Ge5  1  0.176  0.885  0.238  1.0
  O  O6  1  0.692  0.373  0.643  1.0
  O  O7  1  0.308  0.873  0.357  1.0
  O  O8  1  0.816  0.454  0.057  1.0
  O  O9  1  0.184  0.954  0.943  1.0
  O  O10  1  0.962  0.332  0.675  1.0
  O  O11  1  0.038  0.832  0.325  1.0
  O  O12  1  0.859  0.791  0.799  1.0
  O  O13  1  0.141  0.291  0.201  1.0
  O  O14  1  0.719  0.609  0.116  1.0
  O  O15  1  0.281  0.109  0.884  1.0
  O  O16  1  0.482  0.683  0.627  1.0
  O  O17  1  0.518  0.183  0.373  1.0
  O  O18  1  0.587  0.016  0.300  1.0
  O  O19  1  0.413  0.516  0.700  1.0
  O  O20  1  0.617  0.525  0.036  1.0
  O  O21  1  0.383  0.025  0.964  1.0
  O  O22  1  0.777  0.973  0.860  1.0
  O  O23  1  0.223  0.473  0.140  1.0
[/CIF]
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