The material structure described by Na2Si2O5 crystallizes in the orthorhombic Pca2_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(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form corner-sharing SiO4 tetrahedra. There are five 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 Si(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one Si(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Na(1), one Si(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Na(1), one Na(2), one Si(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Na(2), one Si(1), and one Si(2) atom. is represented by the CIF card [CIF]
data_Na2Si2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.651
_cell_length_b   8.464
_cell_length_c   9.536
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   456.107
_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  0.062  0.478  0.011  1.0
  Na  Na1  1  0.087  0.753  0.754  1.0
  Na  Na2  1  0.913  0.753  0.254  1.0
  Na  Na3  1  0.913  0.253  0.246  1.0
  Na  Na4  1  0.938  0.478  0.511  1.0
  Na  Na5  1  0.062  0.978  0.489  1.0
  Na  Na6  1  0.938  0.978  0.989  1.0
  Na  Na7  1  0.087  0.253  0.746  1.0
  Si  Si8  1  0.549  0.249  0.953  1.0
  Si  Si9  1  0.370  0.057  0.192  1.0
  Si  Si10  1  0.370  0.557  0.308  1.0
  Si  Si11  1  0.630  0.557  0.808  1.0
  Si  Si12  1  0.451  0.249  0.453  1.0
  Si  Si13  1  0.549  0.749  0.547  1.0
  Si  Si14  1  0.630  0.057  0.692  1.0
  Si  Si15  1  0.451  0.749  0.047  1.0
  O  O16  1  0.891  0.002  0.733  1.0
  O  O17  1  0.181  0.747  0.999  1.0
  O  O18  1  0.642  0.709  0.920  1.0
  O  O19  1  0.819  0.247  0.001  1.0
  O  O20  1  0.358  0.709  0.420  1.0
  O  O21  1  0.458  0.421  0.885  1.0
  O  O22  1  0.109  0.002  0.233  1.0
  O  O23  1  0.473  0.620  0.672  1.0
  O  O24  1  0.358  0.209  0.080  1.0
  O  O25  1  0.527  0.120  0.328  1.0
  O  O26  1  0.473  0.120  0.828  1.0
  O  O27  1  0.891  0.502  0.767  1.0
  O  O28  1  0.109  0.502  0.267  1.0
  O  O29  1  0.542  0.421  0.385  1.0
  O  O30  1  0.181  0.247  0.501  1.0
  O  O31  1  0.527  0.620  0.172  1.0
  O  O32  1  0.819  0.747  0.499  1.0
  O  O33  1  0.542  0.921  0.115  1.0
  O  O34  1  0.642  0.209  0.580  1.0
  O  O35  1  0.458  0.921  0.615  1.0
[/CIF]
.
The material structure described by Na2Si2O5 crystallizes in the orthorhombic Pca2_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(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form corner-sharing SiO4 tetrahedra. There are five 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 Si(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Na(2), and one Si(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Na(1), one Si(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Na(1), one Na(2), one Si(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Na(2), one Si(1), and one Si(2) atom. is represented by the CIF card [CIF]
data_Na2Si2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.651
_cell_length_b   8.464
_cell_length_c   9.536
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   456.107
_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  0.062  0.478  0.011  1.0
  Na  Na1  1  0.087  0.753  0.754  1.0
  Na  Na2  1  0.913  0.753  0.254  1.0
  Na  Na3  1  0.913  0.253  0.246  1.0
  Na  Na4  1  0.938  0.478  0.511  1.0
  Na  Na5  1  0.062  0.978  0.489  1.0
  Na  Na6  1  0.938  0.978  0.989  1.0
  Na  Na7  1  0.087  0.253  0.746  1.0
  Si  Si8  1  0.549  0.249  0.953  1.0
  Si  Si9  1  0.370  0.057  0.192  1.0
  Si  Si10  1  0.370  0.557  0.308  1.0
  Si  Si11  1  0.630  0.557  0.808  1.0
  Si  Si12  1  0.451  0.249  0.453  1.0
  Si  Si13  1  0.549  0.749  0.547  1.0
  Si  Si14  1  0.630  0.057  0.692  1.0
  Si  Si15  1  0.451  0.749  0.047  1.0
  O  O16  1  0.891  0.002  0.733  1.0
  O  O17  1  0.181  0.747  0.999  1.0
  O  O18  1  0.642  0.709  0.920  1.0
  O  O19  1  0.819  0.247  0.001  1.0
  O  O20  1  0.358  0.709  0.420  1.0
  O  O21  1  0.458  0.421  0.885  1.0
  O  O22  1  0.109  0.002  0.233  1.0
  O  O23  1  0.473  0.620  0.672  1.0
  O  O24  1  0.358  0.209  0.080  1.0
  O  O25  1  0.527  0.120  0.328  1.0
  O  O26  1  0.473  0.120  0.828  1.0
  O  O27  1  0.891  0.502  0.767  1.0
  O  O28  1  0.109  0.502  0.267  1.0
  O  O29  1  0.542  0.421  0.385  1.0
  O  O30  1  0.181  0.247  0.501  1.0
  O  O31  1  0.527  0.620  0.172  1.0
  O  O32  1  0.819  0.747  0.499  1.0
  O  O33  1  0.542  0.921  0.115  1.0
  O  O34  1  0.642  0.209  0.580  1.0
  O  O35  1  0.458  0.921  0.615  1.0
[/CIF]
.