The crystal structure described by CsSr2MgNb3O10 crystallizes in the orthorhombic Pmm2 space group. Cs(1) is bonded in a 8-coordinate geometry to four equivalent Mg(1) and four equivalent O(1) atoms. Sr(1) is bonded to two equivalent O(2), two equivalent O(3), two equivalent O(4), two equivalent O(5), and four equivalent O(6) atoms to form SrO12 cuboctahedra that share corners with eight equivalent Sr(1)O12 cuboctahedra, faces with five equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Nb(1)O6 octahedra, and faces with four equivalent Nb(2)O6 octahedra. Mg(1) is bonded in a bent 120 degrees geometry to four equivalent Cs(1) and two equivalent O(1) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(3) atoms to form NbO6 octahedra that share  a cornercorner with one Nb(2)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-15°. In the second Nb site, Nb(2) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, and faces with eight equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-5°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Cs(1), one Mg(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to two equivalent Sr(1) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to four equivalent Sr(1) and two equivalent Nb(2) atoms. In the fifth O site, O(5) is bonded in a distorted linear geometry to four equivalent Sr(1) and two equivalent Nb(2) atoms. In the sixth O site, O(6) is bonded in a distorted linear geometry to four equivalent Sr(1), one Nb(1), and one Nb(2) atom. is represented by the CIF file [CIF]
data_CsSr2MgNb3O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.119
_cell_length_b   4.130
_cell_length_c   15.434
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   262.555
_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
  Cs  Cs0  1  0.500  0.277  0.500  1.0
  Sr  Sr1  1  0.500  0.500  0.860  1.0
  Sr  Sr2  1  0.500  0.500  0.140  1.0
  Mg  Mg3  1  0.000  0.802  0.500  1.0
  Nb  Nb4  1  0.000  0.001  0.733  1.0
  Nb  Nb5  1  0.000  0.001  0.267  1.0
  Nb  Nb6  1  0.000  0.003  0.000  1.0
  O  O7  1  0.000  0.023  0.610  1.0
  O  O8  1  0.000  0.023  0.390  1.0
  O  O9  1  0.500  0.006  0.750  1.0
  O  O10  1  0.000  0.515  0.750  1.0
  O  O11  1  0.500  0.006  0.250  1.0
  O  O12  1  0.000  0.515  0.250  1.0
  O  O13  1  0.000  0.512  0.000  1.0
  O  O14  1  0.500  0.005  0.000  1.0
  O  O15  1  0.000  0.022  0.128  1.0
  O  O16  1  0.000  0.022  0.872  1.0
[/CIF]
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The crystal structure described by CsSr2MgNb3O10 crystallizes in the orthorhombic Pmm2 space group. Cs(1) is bonded in a 8-coordinate geometry to four equivalent Mg(1) and four equivalent O(1) atoms. Sr(1) is bonded to two equivalent O(2), two equivalent O(3), two equivalent O(4), two equivalent O(5), and four equivalent O(6) atoms to form SrO12 cuboctahedra that share corners with eight equivalent Sr(1)O12 cuboctahedra, faces with five equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Nb(1)O6 octahedra, and faces with four equivalent Nb(2)O6 octahedra. Mg(1) is bonded in a bent 120 degrees geometry to four equivalent Cs(1) and two equivalent O(1) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(3) atoms to form NbO6 octahedra that share  a cornercorner with one Nb(2)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-15°. In the second Nb site, Nb(2) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, and faces with eight equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-5°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Cs(1), one Mg(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to two equivalent Sr(1) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(1) and two equivalent Nb(1) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to four equivalent Sr(1) and two equivalent Nb(2) atoms. In the fifth O site, O(5) is bonded in a distorted linear geometry to four equivalent Sr(1) and two equivalent Nb(2) atoms. In the sixth O site, O(6) is bonded in a distorted linear geometry to four equivalent Sr(1), one Nb(1), and one Nb(2) atom. is represented by the CIF file [CIF]
data_CsSr2MgNb3O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.119
_cell_length_b   4.130
_cell_length_c   15.434
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   262.555
_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
  Cs  Cs0  1  0.500  0.277  0.500  1.0
  Sr  Sr1  1  0.500  0.500  0.860  1.0
  Sr  Sr2  1  0.500  0.500  0.140  1.0
  Mg  Mg3  1  0.000  0.802  0.500  1.0
  Nb  Nb4  1  0.000  0.001  0.733  1.0
  Nb  Nb5  1  0.000  0.001  0.267  1.0
  Nb  Nb6  1  0.000  0.003  0.000  1.0
  O  O7  1  0.000  0.023  0.610  1.0
  O  O8  1  0.000  0.023  0.390  1.0
  O  O9  1  0.500  0.006  0.750  1.0
  O  O10  1  0.000  0.515  0.750  1.0
  O  O11  1  0.500  0.006  0.250  1.0
  O  O12  1  0.000  0.515  0.250  1.0
  O  O13  1  0.000  0.512  0.000  1.0
  O  O14  1  0.500  0.005  0.000  1.0
  O  O15  1  0.000  0.022  0.128  1.0
  O  O16  1  0.000  0.022  0.872  1.0
[/CIF]
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