The structure described by NaY2F7 crystallizes in the monoclinic C2/m space group. Na(1) is bonded in a body-centered cubic geometry to two equivalent F(2) and six equivalent F(4) atoms. Y(1) is bonded in a body-centered cubic geometry to one F(3), one F(4), three equivalent F(1), and three equivalent F(2) atoms. There are four inequivalent F sites. In the first F site, F(1) is bonded in a trigonal planar geometry to three equivalent Y(1) atoms. In the second F site, F(2) is bonded to one Na(1) and three equivalent Y(1) atoms to form FNaY3 tetrahedra that share corners with three equivalent F(4)Na3Y tetrahedra, corners with seven equivalent F(2)NaY3 tetrahedra, and edges with three equivalent F(4)Na3Y tetrahedra. In the third F site, F(3) is bonded in a linear geometry to two equivalent Y(1) atoms. In the fourth F site, F(4) is bonded to three equivalent Na(1) and one Y(1) atom to form FNa3Y tetrahedra that share corners with three equivalent F(2)NaY3 tetrahedra, corners with nine equivalent F(4)Na3Y tetrahedra, edges with three equivalent F(4)Na3Y tetrahedra, and edges with three equivalent F(2)NaY3 tetrahedra. is represented by the CIF card [CIF]
data_NaY2F7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.987
_cell_length_b   3.987
_cell_length_c   10.910
_cell_angle_alpha   79.940
_cell_angle_beta   79.940
_cell_angle_gamma   59.971
_symmetry_Int_Tables_number   1
_cell_volume   147.087
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Y  Y1  1  0.586  0.586  0.293  1.0
  Y  Y2  1  0.414  0.414  0.707  1.0
  F  F3  1  0.238  0.238  0.334  1.0
  F  F4  1  0.066  0.066  0.756  1.0
  F  F5  1  0.500  0.500  0.500  1.0
  F  F6  1  0.762  0.762  0.666  1.0
  F  F7  1  0.642  0.642  0.092  1.0
  F  F8  1  0.358  0.358  0.908  1.0
  F  F9  1  0.934  0.934  0.244  1.0
[/CIF]
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The structure described by NaY2F7 crystallizes in the monoclinic C2/m space group. Na(1) is bonded in a body-centered cubic geometry to two equivalent F(2) and six equivalent F(4) atoms. Y(1) is bonded in a body-centered cubic geometry to one F(3), one F(4), three equivalent F(1), and three equivalent F(2) atoms. There are four inequivalent F sites. In the first F site, F(1) is bonded in a trigonal planar geometry to three equivalent Y(1) atoms. In the second F site, F(2) is bonded to one Na(1) and three equivalent Y(1) atoms to form FNaY3 tetrahedra that share corners with three equivalent F(4)Na3Y tetrahedra, corners with seven equivalent F(2)NaY3 tetrahedra, and edges with three equivalent F(4)Na3Y tetrahedra. In the third F site, F(3) is bonded in a linear geometry to two equivalent Y(1) atoms. In the fourth F site, F(4) is bonded to three equivalent Na(1) and one Y(1) atom to form FNa3Y tetrahedra that share corners with three equivalent F(2)NaY3 tetrahedra, corners with nine equivalent F(4)Na3Y tetrahedra, edges with three equivalent F(4)Na3Y tetrahedra, and edges with three equivalent F(2)NaY3 tetrahedra. is represented by the CIF card [CIF]
data_NaY2F7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.987
_cell_length_b   3.987
_cell_length_c   10.910
_cell_angle_alpha   79.940
_cell_angle_beta   79.940
_cell_angle_gamma   59.971
_symmetry_Int_Tables_number   1
_cell_volume   147.087
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Y  Y1  1  0.586  0.586  0.293  1.0
  Y  Y2  1  0.414  0.414  0.707  1.0
  F  F3  1  0.238  0.238  0.334  1.0
  F  F4  1  0.066  0.066  0.756  1.0
  F  F5  1  0.500  0.500  0.500  1.0
  F  F6  1  0.762  0.762  0.666  1.0
  F  F7  1  0.642  0.642  0.092  1.0
  F  F8  1  0.358  0.358  0.908  1.0
  F  F9  1  0.934  0.934  0.244  1.0
[/CIF]
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