The material structure described by NaCaMg2F7 crystallizes in the orthorhombic Imma space group. Na(1) is bonded to two equivalent F(1), two equivalent F(4), and four equivalent F(3) atoms to form distorted NaF8 hexagonal bipyramids that share edges with two equivalent Na(1)F8 hexagonal bipyramids, edges with four equivalent Ca(1)F8 hexagonal bipyramids, edges with two equivalent Mg(1)F6 octahedra, and edges with four equivalent Mg(2)F6 octahedra. Ca(1) is bonded to two equivalent F(2), two equivalent F(4), and four equivalent F(3) atoms to form distorted CaF8 hexagonal bipyramids that share edges with two equivalent Ca(1)F8 hexagonal bipyramids, edges with four equivalent Na(1)F8 hexagonal bipyramids, edges with two equivalent Mg(2)F6 octahedra, and edges with four equivalent Mg(1)F6 octahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent F(2) and four equivalent F(3) atoms to form MgF6 octahedra that share corners with two equivalent Mg(1)F6 octahedra, corners with four equivalent Mg(2)F6 octahedra, edges with two equivalent Na(1)F8 hexagonal bipyramids, and edges with four equivalent Ca(1)F8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 48-50°. In the second Mg site, Mg(2) is bonded to two equivalent F(1) and four equivalent F(3) atoms to form MgF6 octahedra that share corners with two equivalent Mg(2)F6 octahedra, corners with four equivalent Mg(1)F6 octahedra, edges with two equivalent Ca(1)F8 hexagonal bipyramids, and edges with four equivalent Na(1)F8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 43-48°. There are four inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to two equivalent Na(1) and two equivalent Mg(2) atoms. In the second F site, F(2) is bonded to two equivalent Ca(1) and two equivalent Mg(1) atoms to form distorted FCa2Mg2 tetrahedra that share corners with two equivalent F(4)Na2Ca2 tetrahedra, corners with four equivalent F(2)Ca2Mg2 tetrahedra, and  an edgeedge with one F(4)Na2Ca2 tetrahedra. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Mg(1), and one Mg(2) atom. In the fourth F site, F(4) is bonded to two equivalent Na(1) and two equivalent Ca(1) atoms to form FNa2Ca2 tetrahedra that share corners with two equivalent F(2)Ca2Mg2 tetrahedra, corners with four equivalent F(4)Na2Ca2 tetrahedra, and  an edgeedge with one F(2)Ca2Mg2 tetrahedra. is represented by the CIF file [CIF]
data_NaCaMg2F7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.344
_cell_length_b   7.344
_cell_length_c   7.344
_cell_angle_alpha   121.056
_cell_angle_beta   118.825
_cell_angle_gamma   90.113
_symmetry_Int_Tables_number   1
_cell_volume   280.159
_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  0.000  0.500  0.000  1.0
  Na  Na1  1  0.000  0.000  0.500  1.0
  Ca  Ca2  1  0.000  0.500  0.500  1.0
  Ca  Ca3  1  0.500  0.500  0.000  1.0
  Mg  Mg4  1  0.500  0.000  0.000  1.0
  Mg  Mg5  1  0.500  0.500  0.500  1.0
  Mg  Mg6  1  0.500  0.000  0.500  1.0
  Mg  Mg7  1  0.000  0.000  0.000  1.0
  F  F8  1  0.822  0.072  0.750  1.0
  F  F9  1  0.418  0.668  0.750  1.0
  F  F10  1  0.825  0.668  0.738  1.0
  F  F11  1  0.430  0.087  0.762  1.0
  F  F12  1  0.825  0.087  0.157  1.0
  F  F13  1  0.430  0.668  0.343  1.0
  F  F14  1  0.178  0.928  0.250  1.0
  F  F15  1  0.582  0.332  0.250  1.0
  F  F16  1  0.175  0.332  0.262  1.0
  F  F17  1  0.570  0.913  0.238  1.0
  F  F18  1  0.175  0.913  0.843  1.0
  F  F19  1  0.570  0.332  0.657  1.0
  F  F20  1  0.869  0.619  0.250  1.0
  F  F21  1  0.131  0.381  0.750  1.0
[/CIF]
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The material structure described by NaCaMg2F7 crystallizes in the orthorhombic Imma space group. Na(1) is bonded to two equivalent F(1), two equivalent F(4), and four equivalent F(3) atoms to form distorted NaF8 hexagonal bipyramids that share edges with two equivalent Na(1)F8 hexagonal bipyramids, edges with four equivalent Ca(1)F8 hexagonal bipyramids, edges with two equivalent Mg(1)F6 octahedra, and edges with four equivalent Mg(2)F6 octahedra. Ca(1) is bonded to two equivalent F(2), two equivalent F(4), and four equivalent F(3) atoms to form distorted CaF8 hexagonal bipyramids that share edges with two equivalent Ca(1)F8 hexagonal bipyramids, edges with four equivalent Na(1)F8 hexagonal bipyramids, edges with two equivalent Mg(2)F6 octahedra, and edges with four equivalent Mg(1)F6 octahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent F(2) and four equivalent F(3) atoms to form MgF6 octahedra that share corners with two equivalent Mg(1)F6 octahedra, corners with four equivalent Mg(2)F6 octahedra, edges with two equivalent Na(1)F8 hexagonal bipyramids, and edges with four equivalent Ca(1)F8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 48-50°. In the second Mg site, Mg(2) is bonded to two equivalent F(1) and four equivalent F(3) atoms to form MgF6 octahedra that share corners with two equivalent Mg(2)F6 octahedra, corners with four equivalent Mg(1)F6 octahedra, edges with two equivalent Ca(1)F8 hexagonal bipyramids, and edges with four equivalent Na(1)F8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 43-48°. There are four inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to two equivalent Na(1) and two equivalent Mg(2) atoms. In the second F site, F(2) is bonded to two equivalent Ca(1) and two equivalent Mg(1) atoms to form distorted FCa2Mg2 tetrahedra that share corners with two equivalent F(4)Na2Ca2 tetrahedra, corners with four equivalent F(2)Ca2Mg2 tetrahedra, and  an edgeedge with one F(4)Na2Ca2 tetrahedra. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Mg(1), and one Mg(2) atom. In the fourth F site, F(4) is bonded to two equivalent Na(1) and two equivalent Ca(1) atoms to form FNa2Ca2 tetrahedra that share corners with two equivalent F(2)Ca2Mg2 tetrahedra, corners with four equivalent F(4)Na2Ca2 tetrahedra, and  an edgeedge with one F(2)Ca2Mg2 tetrahedra. is represented by the CIF file [CIF]
data_NaCaMg2F7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.344
_cell_length_b   7.344
_cell_length_c   7.344
_cell_angle_alpha   121.056
_cell_angle_beta   118.825
_cell_angle_gamma   90.113
_symmetry_Int_Tables_number   1
_cell_volume   280.159
_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  0.000  0.500  0.000  1.0
  Na  Na1  1  0.000  0.000  0.500  1.0
  Ca  Ca2  1  0.000  0.500  0.500  1.0
  Ca  Ca3  1  0.500  0.500  0.000  1.0
  Mg  Mg4  1  0.500  0.000  0.000  1.0
  Mg  Mg5  1  0.500  0.500  0.500  1.0
  Mg  Mg6  1  0.500  0.000  0.500  1.0
  Mg  Mg7  1  0.000  0.000  0.000  1.0
  F  F8  1  0.822  0.072  0.750  1.0
  F  F9  1  0.418  0.668  0.750  1.0
  F  F10  1  0.825  0.668  0.738  1.0
  F  F11  1  0.430  0.087  0.762  1.0
  F  F12  1  0.825  0.087  0.157  1.0
  F  F13  1  0.430  0.668  0.343  1.0
  F  F14  1  0.178  0.928  0.250  1.0
  F  F15  1  0.582  0.332  0.250  1.0
  F  F16  1  0.175  0.332  0.262  1.0
  F  F17  1  0.570  0.913  0.238  1.0
  F  F18  1  0.175  0.913  0.843  1.0
  F  F19  1  0.570  0.332  0.657  1.0
  F  F20  1  0.869  0.619  0.250  1.0
  F  F21  1  0.131  0.381  0.750  1.0
[/CIF]
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