The material structure described by Na2BeF4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one F(4), two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form distorted NaF7 pentagonal bipyramids that share corners with four equivalent Na(2)F6 octahedra, corners with four equivalent Na(1)F7 pentagonal bipyramids,  a cornercorner with one Be(1)F4 tetrahedra, edges with three equivalent Na(2)F6 octahedra,  an edgeedge with one Na(1)F7 pentagonal bipyramid, and edges with three equivalent Be(1)F4 tetrahedra. The corner-sharing octahedral tilt angles range from 46-69°. In the second Na site, Na(2) is bonded to one F(2), one F(3), two equivalent F(1), and two equivalent F(4) atoms to form distorted NaF6 octahedra that share corners with four equivalent Na(1)F7 pentagonal bipyramids, corners with four equivalent Be(1)F4 tetrahedra, edges with two equivalent Na(2)F6 octahedra, edges with three equivalent Na(1)F7 pentagonal bipyramids, and  an edgeedge with one Be(1)F4 tetrahedra. Be(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form BeF4 tetrahedra that share corners with four equivalent Na(2)F6 octahedra,  a cornercorner with one Na(1)F7 pentagonal bipyramid,  an edgeedge with one Na(2)F6 octahedra, and edges with three equivalent Na(1)F7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 5-50°. There are four inequivalent F sites. In the first F site, F(1) is bonded to two equivalent Na(1), two equivalent Na(2), and one Be(1) atom to form a mixture of distorted corner and edge-sharing FNa4Be trigonal bipyramids. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), and one Be(1) atom. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), and one Be(1) atom. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Na(2), and one Be(1) atom. is represented by the CIF card [CIF]
data_Na2BeF4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.914
_cell_length_b   5.505
_cell_length_c   8.731
_cell_angle_alpha   61.611
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   334.603
_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  0.343  0.414  0.373  1.0
  Na  Na1  1  0.843  0.586  0.127  1.0
  Na  Na2  1  0.657  0.586  0.627  1.0
  Na  Na3  1  0.157  0.414  0.873  1.0
  Na  Na4  1  0.486  0.147  0.133  1.0
  Na  Na5  1  0.986  0.853  0.367  1.0
  Na  Na6  1  0.514  0.853  0.867  1.0
  Na  Na7  1  0.014  0.147  0.633  1.0
  Be  Be8  1  0.305  0.754  0.537  1.0
  Be  Be9  1  0.695  0.246  0.463  1.0
  Be  Be10  1  0.195  0.754  0.037  1.0
  Be  Be11  1  0.805  0.246  0.963  1.0
  F  F12  1  0.818  0.487  0.432  1.0
  F  F13  1  0.318  0.513  0.068  1.0
  F  F14  1  0.182  0.513  0.568  1.0
  F  F15  1  0.682  0.487  0.932  1.0
  F  F16  1  0.936  0.212  0.103  1.0
  F  F17  1  0.564  0.212  0.603  1.0
  F  F18  1  0.436  0.788  0.397  1.0
  F  F19  1  0.064  0.788  0.897  1.0
  F  F20  1  0.894  0.326  0.789  1.0
  F  F21  1  0.394  0.674  0.711  1.0
  F  F22  1  0.106  0.674  0.211  1.0
  F  F23  1  0.606  0.326  0.289  1.0
  F  F24  1  0.695  0.981  0.022  1.0
  F  F25  1  0.195  0.019  0.478  1.0
  F  F26  1  0.305  0.019  0.978  1.0
  F  F27  1  0.805  0.981  0.522  1.0
[/CIF]
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The material structure described by Na2BeF4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one F(4), two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form distorted NaF7 pentagonal bipyramids that share corners with four equivalent Na(2)F6 octahedra, corners with four equivalent Na(1)F7 pentagonal bipyramids,  a cornercorner with one Be(1)F4 tetrahedra, edges with three equivalent Na(2)F6 octahedra,  an edgeedge with one Na(1)F7 pentagonal bipyramid, and edges with three equivalent Be(1)F4 tetrahedra. The corner-sharing octahedral tilt angles range from 46-69°. In the second Na site, Na(2) is bonded to one F(2), one F(3), two equivalent F(1), and two equivalent F(4) atoms to form distorted NaF6 octahedra that share corners with four equivalent Na(1)F7 pentagonal bipyramids, corners with four equivalent Be(1)F4 tetrahedra, edges with two equivalent Na(2)F6 octahedra, edges with three equivalent Na(1)F7 pentagonal bipyramids, and  an edgeedge with one Be(1)F4 tetrahedra. Be(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form BeF4 tetrahedra that share corners with four equivalent Na(2)F6 octahedra,  a cornercorner with one Na(1)F7 pentagonal bipyramid,  an edgeedge with one Na(2)F6 octahedra, and edges with three equivalent Na(1)F7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 5-50°. There are four inequivalent F sites. In the first F site, F(1) is bonded to two equivalent Na(1), two equivalent Na(2), and one Be(1) atom to form a mixture of distorted corner and edge-sharing FNa4Be trigonal bipyramids. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), and one Be(1) atom. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), and one Be(1) atom. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Na(2), and one Be(1) atom. is represented by the CIF card [CIF]
data_Na2BeF4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.914
_cell_length_b   5.505
_cell_length_c   8.731
_cell_angle_alpha   61.611
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   334.603
_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  0.343  0.414  0.373  1.0
  Na  Na1  1  0.843  0.586  0.127  1.0
  Na  Na2  1  0.657  0.586  0.627  1.0
  Na  Na3  1  0.157  0.414  0.873  1.0
  Na  Na4  1  0.486  0.147  0.133  1.0
  Na  Na5  1  0.986  0.853  0.367  1.0
  Na  Na6  1  0.514  0.853  0.867  1.0
  Na  Na7  1  0.014  0.147  0.633  1.0
  Be  Be8  1  0.305  0.754  0.537  1.0
  Be  Be9  1  0.695  0.246  0.463  1.0
  Be  Be10  1  0.195  0.754  0.037  1.0
  Be  Be11  1  0.805  0.246  0.963  1.0
  F  F12  1  0.818  0.487  0.432  1.0
  F  F13  1  0.318  0.513  0.068  1.0
  F  F14  1  0.182  0.513  0.568  1.0
  F  F15  1  0.682  0.487  0.932  1.0
  F  F16  1  0.936  0.212  0.103  1.0
  F  F17  1  0.564  0.212  0.603  1.0
  F  F18  1  0.436  0.788  0.397  1.0
  F  F19  1  0.064  0.788  0.897  1.0
  F  F20  1  0.894  0.326  0.789  1.0
  F  F21  1  0.394  0.674  0.711  1.0
  F  F22  1  0.106  0.674  0.211  1.0
  F  F23  1  0.606  0.326  0.289  1.0
  F  F24  1  0.695  0.981  0.022  1.0
  F  F25  1  0.195  0.019  0.478  1.0
  F  F26  1  0.305  0.019  0.978  1.0
  F  F27  1  0.805  0.981  0.522  1.0
[/CIF]
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