The crystal structure described by NaBSi2O7 crystallizes in the monoclinic P2_1 space group. Na(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), two equivalent O(6), and two equivalent O(7) atoms. B(1) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form BO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and  a cornercorner with one Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one B(1)O4 tetrahedra and corners with three equivalent Si(2)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one B(1)O4 tetrahedra and corners with three equivalent Si(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Na(1), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Na(1), one B(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 B(1), and one Si(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Na(1) and one B(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Na(1) and one B(1) atom. is represented by the CIF card [CIF]
data_NaSi2BO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.953
_cell_length_b   7.222
_cell_length_c   8.178
_cell_angle_alpha   90.000
_cell_angle_beta   93.352
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   292.049
_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  0.986  0.496  0.442  1.0
  Na  Na1  1  0.014  0.996  0.558  1.0
  Si  Si2  1  0.213  0.908  0.133  1.0
  Si  Si3  1  0.787  0.408  0.867  1.0
  Si  Si4  1  0.305  0.485  0.081  1.0
  Si  Si5  1  0.695  0.985  0.919  1.0
  B  B6  1  0.383  0.203  0.339  1.0
  B  B7  1  0.617  0.703  0.661  1.0
  O  O8  1  0.247  0.686  0.164  1.0
  O  O9  1  0.753  0.186  0.836  1.0
  O  O10  1  0.896  0.952  0.081  1.0
  O  O11  1  0.104  0.452  0.919  1.0
  O  O12  1  0.257  0.332  0.220  1.0
  O  O13  1  0.743  0.832  0.780  1.0
  O  O14  1  0.301  0.012  0.303  1.0
  O  O15  1  0.699  0.512  0.697  1.0
  O  O16  1  0.613  0.479  0.019  1.0
  O  O17  1  0.387  0.979  0.981  1.0
  O  O18  1  0.671  0.224  0.380  1.0
  O  O19  1  0.329  0.724  0.620  1.0
  O  O20  1  0.676  0.750  0.494  1.0
  O  O21  1  0.324  0.250  0.506  1.0
[/CIF]
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The crystal structure described by NaBSi2O7 crystallizes in the monoclinic P2_1 space group. Na(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(4), two equivalent O(6), and two equivalent O(7) atoms. B(1) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form BO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and  a cornercorner with one Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one B(1)O4 tetrahedra and corners with three equivalent Si(2)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one B(1)O4 tetrahedra and corners with three equivalent Si(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Na(1), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Na(1), one B(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 B(1), and one Si(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Na(1) and one B(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Na(1) and one B(1) atom. is represented by the CIF card [CIF]
data_NaSi2BO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.953
_cell_length_b   7.222
_cell_length_c   8.178
_cell_angle_alpha   90.000
_cell_angle_beta   93.352
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   292.049
_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  0.986  0.496  0.442  1.0
  Na  Na1  1  0.014  0.996  0.558  1.0
  Si  Si2  1  0.213  0.908  0.133  1.0
  Si  Si3  1  0.787  0.408  0.867  1.0
  Si  Si4  1  0.305  0.485  0.081  1.0
  Si  Si5  1  0.695  0.985  0.919  1.0
  B  B6  1  0.383  0.203  0.339  1.0
  B  B7  1  0.617  0.703  0.661  1.0
  O  O8  1  0.247  0.686  0.164  1.0
  O  O9  1  0.753  0.186  0.836  1.0
  O  O10  1  0.896  0.952  0.081  1.0
  O  O11  1  0.104  0.452  0.919  1.0
  O  O12  1  0.257  0.332  0.220  1.0
  O  O13  1  0.743  0.832  0.780  1.0
  O  O14  1  0.301  0.012  0.303  1.0
  O  O15  1  0.699  0.512  0.697  1.0
  O  O16  1  0.613  0.479  0.019  1.0
  O  O17  1  0.387  0.979  0.981  1.0
  O  O18  1  0.671  0.224  0.380  1.0
  O  O19  1  0.329  0.724  0.620  1.0
  O  O20  1  0.676  0.750  0.494  1.0
  O  O21  1  0.324  0.250  0.506  1.0
[/CIF]
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