The material described by MgNb3O7F crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form MgO5 trigonal bipyramids that share corners with two equivalent Mg(1)O5 trigonal bipyramids, edges with two equivalent Nb(1)O6 octahedra, edges with two equivalent Nb(2)O6F pentagonal bipyramids, and edges with two equivalent Nb(3)O6F pentagonal bipyramids. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(6), one O(7), and two equivalent O(3) atoms to form distorted NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6F pentagonal bipyramids, corners with two equivalent Nb(3)O6F pentagonal bipyramids,  an edgeedge with one Nb(2)O6F pentagonal bipyramid,  an edgeedge with one Nb(3)O6F pentagonal bipyramid, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 18°. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), one O(6), one O(7), two equivalent O(4), and one F(1) atom to form NbO6F pentagonal bipyramids that share corners with two equivalent Nb(1)O6 octahedra,  a cornercorner with one Nb(3)O6F pentagonal bipyramid, corners with two equivalent Nb(2)O6F pentagonal bipyramids,  an edgeedge with one Nb(1)O6 octahedra, edges with two equivalent Nb(3)O6F pentagonal bipyramids, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 35-43°. In the third Nb site, Nb(3) is bonded to one O(1), one O(2), one O(6), one O(7), two equivalent O(5), and one F(1) atom to form NbO6F pentagonal bipyramids that share corners with two equivalent Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6F pentagonal bipyramid, corners with two equivalent Nb(3)O6F pentagonal bipyramids,  an edgeedge with one Nb(1)O6 octahedra, edges with two equivalent Nb(2)O6F pentagonal bipyramids, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 34-41°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Nb(1), one Nb(2), and one Nb(3) atom to form corner-sharing OMg2Nb3 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Nb(1), one Nb(2), and one Nb(3) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Mg(1) and two equivalent Nb(2) atoms. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Mg(1) and two equivalent Nb(3) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Nb(3) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Nb(1), one Nb(2), and one Nb(3) atom. F(1) is bonded in a linear geometry to one Nb(2) and one Nb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgNb3O7F
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.504
_cell_length_b   6.546
_cell_length_c   4.007
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   61.230
_symmetry_Int_Tables_number   1
_cell_volume   149.533
_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
  Mg  Mg0  1  0.043  0.656  0.500  1.0
  Nb  Nb1  1  0.986  0.032  0.000  1.0
  Nb  Nb2  1  0.322  0.279  0.000  1.0
  Nb  Nb3  1  0.680  0.702  0.000  1.0
  O  O4  1  0.047  0.660  0.000  1.0
  O  O5  1  0.336  0.958  0.000  1.0
  O  O6  1  0.006  0.976  0.500  1.0
  O  O7  1  0.297  0.323  0.500  1.0
  O  O8  1  0.709  0.692  0.500  1.0
  O  O9  1  0.953  0.344  0.000  1.0
  O  O10  1  0.663  0.037  0.000  1.0
  F  F11  1  0.502  0.496  0.000  1.0
[/CIF]
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The material described by MgNb3O7F crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form MgO5 trigonal bipyramids that share corners with two equivalent Mg(1)O5 trigonal bipyramids, edges with two equivalent Nb(1)O6 octahedra, edges with two equivalent Nb(2)O6F pentagonal bipyramids, and edges with two equivalent Nb(3)O6F pentagonal bipyramids. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(6), one O(7), and two equivalent O(3) atoms to form distorted NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with two equivalent Nb(2)O6F pentagonal bipyramids, corners with two equivalent Nb(3)O6F pentagonal bipyramids,  an edgeedge with one Nb(2)O6F pentagonal bipyramid,  an edgeedge with one Nb(3)O6F pentagonal bipyramid, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 18°. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), one O(6), one O(7), two equivalent O(4), and one F(1) atom to form NbO6F pentagonal bipyramids that share corners with two equivalent Nb(1)O6 octahedra,  a cornercorner with one Nb(3)O6F pentagonal bipyramid, corners with two equivalent Nb(2)O6F pentagonal bipyramids,  an edgeedge with one Nb(1)O6 octahedra, edges with two equivalent Nb(3)O6F pentagonal bipyramids, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 35-43°. In the third Nb site, Nb(3) is bonded to one O(1), one O(2), one O(6), one O(7), two equivalent O(5), and one F(1) atom to form NbO6F pentagonal bipyramids that share corners with two equivalent Nb(1)O6 octahedra,  a cornercorner with one Nb(2)O6F pentagonal bipyramid, corners with two equivalent Nb(3)O6F pentagonal bipyramids,  an edgeedge with one Nb(1)O6 octahedra, edges with two equivalent Nb(2)O6F pentagonal bipyramids, and edges with two equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 34-41°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Nb(1), one Nb(2), and one Nb(3) atom to form corner-sharing OMg2Nb3 trigonal bipyramids. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Nb(1), one Nb(2), and one Nb(3) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Mg(1) and two equivalent Nb(2) atoms. In the fifth O site, O(5) is bonded in a T-shaped geometry to one Mg(1) and two equivalent Nb(3) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Nb(3) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Nb(1), one Nb(2), and one Nb(3) atom. F(1) is bonded in a linear geometry to one Nb(2) and one Nb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgNb3O7F
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.504
_cell_length_b   6.546
_cell_length_c   4.007
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   61.230
_symmetry_Int_Tables_number   1
_cell_volume   149.533
_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
  Mg  Mg0  1  0.043  0.656  0.500  1.0
  Nb  Nb1  1  0.986  0.032  0.000  1.0
  Nb  Nb2  1  0.322  0.279  0.000  1.0
  Nb  Nb3  1  0.680  0.702  0.000  1.0
  O  O4  1  0.047  0.660  0.000  1.0
  O  O5  1  0.336  0.958  0.000  1.0
  O  O6  1  0.006  0.976  0.500  1.0
  O  O7  1  0.297  0.323  0.500  1.0
  O  O8  1  0.709  0.692  0.500  1.0
  O  O9  1  0.953  0.344  0.000  1.0
  O  O10  1  0.663  0.037  0.000  1.0
  F  F11  1  0.502  0.496  0.000  1.0
[/CIF]
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