The material described by MgNb5O9 is (Cubic) Perovskite-like structured and crystallizes in the trigonal P-3m1 space group. Mg(1) is bonded to six equivalent O(2) atoms to form MgO6 octahedra that share corners with six equivalent Nb(3)O6 octahedra, faces with two equivalent Nb(1)O12 cuboctahedra, and faces with six equivalent Nb(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 3°. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form NbO12 cuboctahedra that share corners with six equivalent Nb(1)O12 cuboctahedra, corners with six equivalent Nb(2)O12 cuboctahedra, faces with six equivalent Nb(2)O12 cuboctahedra, faces with two equivalent Mg(1)O6 octahedra, and faces with six equivalent Nb(3)O6 octahedra. In the second Nb site, Nb(2) is bonded to three equivalent O(1) and nine equivalent O(2) atoms to form NbO12 cuboctahedra that share corners with three equivalent Nb(1)O12 cuboctahedra, corners with nine equivalent Nb(2)O12 cuboctahedra, faces with three equivalent Nb(1)O12 cuboctahedra, faces with three equivalent Nb(2)O12 cuboctahedra, faces with three equivalent Mg(1)O6 octahedra, and faces with five equivalent Nb(3)O6 octahedra. In the third Nb site, Nb(3) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NbO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Nb(3)O6 octahedra, faces with three equivalent Nb(1)O12 cuboctahedra, and faces with five equivalent Nb(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to two equivalent Nb(1), two equivalent Nb(2), and two equivalent Nb(3) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Mg(1), one Nb(1), one Nb(3), and three equivalent Nb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgNb5O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.624
_cell_length_b   5.624
_cell_length_c   6.853
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   187.700
_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  0.000  0.000  0.500  1.0
  Nb  Nb1  1  0.000  0.000  0.000  1.0
  Nb  Nb2  1  0.667  0.333  0.339  1.0
  Nb  Nb3  1  0.333  0.667  0.181  1.0
  Nb  Nb4  1  0.333  0.667  0.661  1.0
  Nb  Nb5  1  0.667  0.333  0.819  1.0
  O  O6  1  0.500  0.000  0.000  1.0
  O  O7  1  0.500  0.500  0.000  1.0
  O  O8  1  0.670  0.835  0.332  1.0
  O  O9  1  0.165  0.330  0.332  1.0
  O  O10  1  0.165  0.835  0.332  1.0
  O  O11  1  0.330  0.165  0.668  1.0
  O  O12  1  0.835  0.670  0.668  1.0
  O  O13  1  0.835  0.165  0.668  1.0
  O  O14  1  0.000  0.500  0.000  1.0
[/CIF]
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The material described by MgNb5O9 is (Cubic) Perovskite-like structured and crystallizes in the trigonal P-3m1 space group. Mg(1) is bonded to six equivalent O(2) atoms to form MgO6 octahedra that share corners with six equivalent Nb(3)O6 octahedra, faces with two equivalent Nb(1)O12 cuboctahedra, and faces with six equivalent Nb(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 3°. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form NbO12 cuboctahedra that share corners with six equivalent Nb(1)O12 cuboctahedra, corners with six equivalent Nb(2)O12 cuboctahedra, faces with six equivalent Nb(2)O12 cuboctahedra, faces with two equivalent Mg(1)O6 octahedra, and faces with six equivalent Nb(3)O6 octahedra. In the second Nb site, Nb(2) is bonded to three equivalent O(1) and nine equivalent O(2) atoms to form NbO12 cuboctahedra that share corners with three equivalent Nb(1)O12 cuboctahedra, corners with nine equivalent Nb(2)O12 cuboctahedra, faces with three equivalent Nb(1)O12 cuboctahedra, faces with three equivalent Nb(2)O12 cuboctahedra, faces with three equivalent Mg(1)O6 octahedra, and faces with five equivalent Nb(3)O6 octahedra. In the third Nb site, Nb(3) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NbO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Nb(3)O6 octahedra, faces with three equivalent Nb(1)O12 cuboctahedra, and faces with five equivalent Nb(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to two equivalent Nb(1), two equivalent Nb(2), and two equivalent Nb(3) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Mg(1), one Nb(1), one Nb(3), and three equivalent Nb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgNb5O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.624
_cell_length_b   5.624
_cell_length_c   6.853
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   187.700
_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  0.000  0.000  0.500  1.0
  Nb  Nb1  1  0.000  0.000  0.000  1.0
  Nb  Nb2  1  0.667  0.333  0.339  1.0
  Nb  Nb3  1  0.333  0.667  0.181  1.0
  Nb  Nb4  1  0.333  0.667  0.661  1.0
  Nb  Nb5  1  0.667  0.333  0.819  1.0
  O  O6  1  0.500  0.000  0.000  1.0
  O  O7  1  0.500  0.500  0.000  1.0
  O  O8  1  0.670  0.835  0.332  1.0
  O  O9  1  0.165  0.330  0.332  1.0
  O  O10  1  0.165  0.835  0.332  1.0
  O  O11  1  0.330  0.165  0.668  1.0
  O  O12  1  0.835  0.670  0.668  1.0
  O  O13  1  0.835  0.165  0.668  1.0
  O  O14  1  0.000  0.500  0.000  1.0
[/CIF]
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