The crystal structure described by Na4B2O5 crystallizes in the monoclinic C2/c 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), two equivalent O(2), and three equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to two equivalent O(3) and three equivalent O(2) atoms. B(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Na(1) and two equivalent B(1) atoms. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Na(1), three equivalent Na(2), and one B(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to two equivalent Na(2), three equivalent Na(1), and one B(1) atom. is represented by the CIF card [CIF]
data_Na4B2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.619
_cell_length_b   6.619
_cell_length_c   6.197
_cell_angle_alpha   73.765
_cell_angle_beta   73.765
_cell_angle_gamma   73.763
_symmetry_Int_Tables_number   1
_cell_volume   244.255
_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  0.685  0.032  0.773  1.0
  Na  Na1  1  0.968  0.315  0.727  1.0
  Na  Na2  1  0.315  0.968  0.227  1.0
  Na  Na3  1  0.032  0.685  0.273  1.0
  Na  Na4  1  0.404  0.330  0.424  1.0
  Na  Na5  1  0.670  0.596  0.076  1.0
  Na  Na6  1  0.596  0.670  0.576  1.0
  Na  Na7  1  0.330  0.404  0.924  1.0
  B  B8  1  0.253  0.930  0.834  1.0
  B  B9  1  0.070  0.747  0.666  1.0
  B  B10  1  0.747  0.070  0.166  1.0
  B  B11  1  0.930  0.253  0.334  1.0
  O  O12  1  0.929  0.071  0.250  1.0
  O  O13  1  0.071  0.929  0.750  1.0
  O  O14  1  0.742  0.348  0.461  1.0
  O  O15  1  0.652  0.258  0.039  1.0
  O  O16  1  0.315  0.120  0.786  1.0
  O  O17  1  0.880  0.685  0.714  1.0
  O  O18  1  0.685  0.880  0.214  1.0
  O  O19  1  0.120  0.315  0.286  1.0
  O  O20  1  0.348  0.742  0.961  1.0
  O  O21  1  0.258  0.652  0.539  1.0
[/CIF]
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The crystal structure described by Na4B2O5 crystallizes in the monoclinic C2/c 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), two equivalent O(2), and three equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to two equivalent O(3) and three equivalent O(2) atoms. B(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Na(1) and two equivalent B(1) atoms. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Na(1), three equivalent Na(2), and one B(1) atom. In the third O site, O(3) is bonded in a 1-coordinate geometry to two equivalent Na(2), three equivalent Na(1), and one B(1) atom. is represented by the CIF card [CIF]
data_Na4B2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.619
_cell_length_b   6.619
_cell_length_c   6.197
_cell_angle_alpha   73.765
_cell_angle_beta   73.765
_cell_angle_gamma   73.763
_symmetry_Int_Tables_number   1
_cell_volume   244.255
_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  0.685  0.032  0.773  1.0
  Na  Na1  1  0.968  0.315  0.727  1.0
  Na  Na2  1  0.315  0.968  0.227  1.0
  Na  Na3  1  0.032  0.685  0.273  1.0
  Na  Na4  1  0.404  0.330  0.424  1.0
  Na  Na5  1  0.670  0.596  0.076  1.0
  Na  Na6  1  0.596  0.670  0.576  1.0
  Na  Na7  1  0.330  0.404  0.924  1.0
  B  B8  1  0.253  0.930  0.834  1.0
  B  B9  1  0.070  0.747  0.666  1.0
  B  B10  1  0.747  0.070  0.166  1.0
  B  B11  1  0.930  0.253  0.334  1.0
  O  O12  1  0.929  0.071  0.250  1.0
  O  O13  1  0.071  0.929  0.750  1.0
  O  O14  1  0.742  0.348  0.461  1.0
  O  O15  1  0.652  0.258  0.039  1.0
  O  O16  1  0.315  0.120  0.786  1.0
  O  O17  1  0.880  0.685  0.714  1.0
  O  O18  1  0.685  0.880  0.214  1.0
  O  O19  1  0.120  0.315  0.286  1.0
  O  O20  1  0.348  0.742  0.961  1.0
  O  O21  1  0.258  0.652  0.539  1.0
[/CIF]
.