The material described by Sr3Zr2Nb2O12 crystallizes in the trigonal R-3m space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to three equivalent O(2), three equivalent O(3), and six equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with twelve equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(2)O12 cuboctahedra, faces with four equivalent Zr(1)O6 octahedra, and faces with four equivalent Nb(1)O6 octahedra. In the second Sr site, Sr(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form SrO12 cuboctahedra that share corners with six equivalent Sr(2)O12 cuboctahedra, faces with six equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Nb(1)O6 octahedra, and faces with six equivalent Zr(1)O6 octahedra. Zr(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form ZrO6 octahedra that share corners with three equivalent Zr(1)O6 octahedra, corners with three equivalent Nb(1)O6 octahedra, faces with three equivalent Sr(2)O12 cuboctahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-6°. Nb(1) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form NbO6 octahedra that share corners with three equivalent Zr(1)O6 octahedra, corners with three equivalent Nb(1)O6 octahedra,  a faceface with one Sr(2)O12 cuboctahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-6°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Sr(2), two equivalent Sr(1), one Zr(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Zr(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Sr(1) and two equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Sr3Zr2Nb2O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.990
_cell_length_b   9.990
_cell_length_c   9.990
_cell_angle_alpha   34.006
_cell_angle_beta   34.006
_cell_angle_gamma   34.006
_symmetry_Int_Tables_number   1
_cell_volume   277.996
_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
  Sr  Sr0  1  0.751  0.751  0.751  1.0
  Sr  Sr1  1  0.000  0.000  0.000  1.0
  Sr  Sr2  1  0.249  0.249  0.249  1.0
  Zr  Zr3  1  0.378  0.378  0.378  1.0
  Zr  Zr4  1  0.622  0.622  0.622  1.0
  Nb  Nb5  1  0.873  0.873  0.873  1.0
  Nb  Nb6  1  0.127  0.127  0.127  1.0
  O  O7  1  0.760  0.760  0.230  1.0
  O  O8  1  0.500  0.500  0.000  1.0
  O  O9  1  0.240  0.240  0.770  1.0
  O  O10  1  0.000  0.000  0.500  1.0
  O  O11  1  0.770  0.240  0.240  1.0
  O  O12  1  0.500  0.000  0.000  1.0
  O  O13  1  0.230  0.760  0.760  1.0
  O  O14  1  0.000  0.500  0.500  1.0
  O  O15  1  0.240  0.770  0.240  1.0
  O  O16  1  0.000  0.500  0.000  1.0
  O  O17  1  0.760  0.230  0.760  1.0
  O  O18  1  0.500  0.000  0.500  1.0
[/CIF]
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The material described by Sr3Zr2Nb2O12 crystallizes in the trigonal R-3m space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to three equivalent O(2), three equivalent O(3), and six equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with twelve equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(2)O12 cuboctahedra, faces with four equivalent Zr(1)O6 octahedra, and faces with four equivalent Nb(1)O6 octahedra. In the second Sr site, Sr(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form SrO12 cuboctahedra that share corners with six equivalent Sr(2)O12 cuboctahedra, faces with six equivalent Sr(1)O12 cuboctahedra, faces with two equivalent Nb(1)O6 octahedra, and faces with six equivalent Zr(1)O6 octahedra. Zr(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form ZrO6 octahedra that share corners with three equivalent Zr(1)O6 octahedra, corners with three equivalent Nb(1)O6 octahedra, faces with three equivalent Sr(2)O12 cuboctahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-6°. Nb(1) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form NbO6 octahedra that share corners with three equivalent Zr(1)O6 octahedra, corners with three equivalent Nb(1)O6 octahedra,  a faceface with one Sr(2)O12 cuboctahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-6°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Sr(2), two equivalent Sr(1), one Zr(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Zr(1) atoms. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Sr(1) and two equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Sr3Zr2Nb2O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.990
_cell_length_b   9.990
_cell_length_c   9.990
_cell_angle_alpha   34.006
_cell_angle_beta   34.006
_cell_angle_gamma   34.006
_symmetry_Int_Tables_number   1
_cell_volume   277.996
_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
  Sr  Sr0  1  0.751  0.751  0.751  1.0
  Sr  Sr1  1  0.000  0.000  0.000  1.0
  Sr  Sr2  1  0.249  0.249  0.249  1.0
  Zr  Zr3  1  0.378  0.378  0.378  1.0
  Zr  Zr4  1  0.622  0.622  0.622  1.0
  Nb  Nb5  1  0.873  0.873  0.873  1.0
  Nb  Nb6  1  0.127  0.127  0.127  1.0
  O  O7  1  0.760  0.760  0.230  1.0
  O  O8  1  0.500  0.500  0.000  1.0
  O  O9  1  0.240  0.240  0.770  1.0
  O  O10  1  0.000  0.000  0.500  1.0
  O  O11  1  0.770  0.240  0.240  1.0
  O  O12  1  0.500  0.000  0.000  1.0
  O  O13  1  0.230  0.760  0.760  1.0
  O  O14  1  0.000  0.500  0.500  1.0
  O  O15  1  0.240  0.770  0.240  1.0
  O  O16  1  0.000  0.500  0.000  1.0
  O  O17  1  0.760  0.230  0.760  1.0
  O  O18  1  0.500  0.000  0.500  1.0
[/CIF]
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