The material described by Ba3SrSn12 crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent Sn(2), two equivalent Sn(6), two equivalent Sn(7), two equivalent Sn(8), and four equivalent Sn(4) atoms to form distorted BaSn12 cuboctahedra that share corners with two equivalent Ba(1)Sn12 cuboctahedra, corners with four equivalent Sr(1)Sn12 cuboctahedra, faces with two equivalent Ba(1)Sn12 cuboctahedra, faces with two equivalent Ba(2)Sn12 cuboctahedra, and faces with four equivalent Ba(3)Sn12 cuboctahedra. In the second Ba site, Ba(2) is bonded to two equivalent Sn(1), two equivalent Sn(3), two equivalent Sn(4), two equivalent Sn(5), and four equivalent Sn(7) atoms to form distorted BaSn12 cuboctahedra that share corners with two equivalent Ba(2)Sn12 cuboctahedra, corners with four equivalent Ba(3)Sn12 cuboctahedra, faces with two equivalent Ba(1)Sn12 cuboctahedra, faces with two equivalent Ba(2)Sn12 cuboctahedra, and faces with four equivalent Sr(1)Sn12 cuboctahedra. In the third Ba site, Ba(3) is bonded to two equivalent Sn(2), two equivalent Sn(3), two equivalent Sn(4), two equivalent Sn(6), and four equivalent Sn(8) atoms to form distorted BaSn12 cuboctahedra that share corners with two equivalent Ba(3)Sn12 cuboctahedra, corners with four equivalent Ba(2)Sn12 cuboctahedra, faces with two equivalent Ba(3)Sn12 cuboctahedra, faces with two equivalent Sr(1)Sn12 cuboctahedra, and faces with four equivalent Ba(1)Sn12 cuboctahedra. Sr(1) is bonded to two equivalent Sn(1), two equivalent Sn(5), two equivalent Sn(7), two equivalent Sn(8), and four equivalent Sn(3) atoms to form distorted SrSn12 cuboctahedra that share corners with two equivalent Sr(1)Sn12 cuboctahedra, corners with four equivalent Ba(1)Sn12 cuboctahedra, faces with two equivalent Ba(3)Sn12 cuboctahedra, faces with two equivalent Sr(1)Sn12 cuboctahedra, and faces with four equivalent Ba(2)Sn12 cuboctahedra. There are eight inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 10-coordinate geometry to two equivalent Ba(2), two equivalent Sr(1), two equivalent Sn(4), and four equivalent Sn(7) atoms. In the second Sn site, Sn(2) is bonded in a 10-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), two equivalent Sn(3), and four equivalent Sn(8) atoms. In the third Sn site, Sn(3) is bonded in a 10-coordinate geometry to one Ba(2), one Ba(3), two equivalent Sr(1), one Sn(2), one Sn(3), two equivalent Sn(5), and two equivalent Sn(8) atoms. In the fourth Sn site, Sn(4) is bonded in a 10-coordinate geometry to one Ba(2), one Ba(3), two equivalent Ba(1), one Sn(1), one Sn(4), two equivalent Sn(6), and two equivalent Sn(7) atoms. In the fifth Sn site, Sn(5) is bonded in a 10-coordinate geometry to two equivalent Ba(2), two equivalent Sr(1), two equivalent Sn(8), and four equivalent Sn(3) atoms. In the sixth Sn site, Sn(6) is bonded in a 10-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), two equivalent Sn(7), and four equivalent Sn(4) atoms. In the seventh Sn site, Sn(7) is bonded in a 10-coordinate geometry to one Ba(1), two equivalent Ba(2), one Sr(1), one Sn(6), one Sn(7), two equivalent Sn(1), and two equivalent Sn(4) atoms. In the eighth Sn site, Sn(8) is bonded in a 10-coordinate geometry to one Ba(1), two equivalent Ba(3), one Sr(1), one Sn(5), one Sn(8), two equivalent Sn(2), and two equivalent Sn(3) atoms. is represented by the CIF file [CIF]
data_Ba3SrSn12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.341
_cell_length_b   7.354
_cell_length_c   12.980
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   509.857
_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
  Ba  Ba0  1  0.000  0.000  0.667  1.0
  Ba  Ba1  1  0.500  0.000  0.333  1.0
  Ba  Ba2  1  0.500  0.500  0.834  1.0
  Sr  Sr3  1  0.000  0.500  0.167  1.0
  Sn  Sn4  1  0.500  0.500  0.354  1.0
  Sn  Sn5  1  0.500  0.000  0.859  1.0
  Sn  Sn6  1  0.500  0.782  0.073  1.0
  Sn  Sn7  1  0.500  0.288  0.570  1.0
  Sn  Sn8  1  0.500  0.218  0.073  1.0
  Sn  Sn9  1  0.500  0.712  0.570  1.0
  Sn  Sn10  1  0.000  0.000  0.143  1.0
  Sn  Sn11  1  0.000  0.500  0.642  1.0
  Sn  Sn12  1  0.000  0.712  0.428  1.0
  Sn  Sn13  1  0.000  0.214  0.930  1.0
  Sn  Sn14  1  0.000  0.288  0.428  1.0
  Sn  Sn15  1  0.000  0.786  0.930  1.0
[/CIF]
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The material described by Ba3SrSn12 crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent Sn(2), two equivalent Sn(6), two equivalent Sn(7), two equivalent Sn(8), and four equivalent Sn(4) atoms to form distorted BaSn12 cuboctahedra that share corners with two equivalent Ba(1)Sn12 cuboctahedra, corners with four equivalent Sr(1)Sn12 cuboctahedra, faces with two equivalent Ba(1)Sn12 cuboctahedra, faces with two equivalent Ba(2)Sn12 cuboctahedra, and faces with four equivalent Ba(3)Sn12 cuboctahedra. In the second Ba site, Ba(2) is bonded to two equivalent Sn(1), two equivalent Sn(3), two equivalent Sn(4), two equivalent Sn(5), and four equivalent Sn(7) atoms to form distorted BaSn12 cuboctahedra that share corners with two equivalent Ba(2)Sn12 cuboctahedra, corners with four equivalent Ba(3)Sn12 cuboctahedra, faces with two equivalent Ba(1)Sn12 cuboctahedra, faces with two equivalent Ba(2)Sn12 cuboctahedra, and faces with four equivalent Sr(1)Sn12 cuboctahedra. In the third Ba site, Ba(3) is bonded to two equivalent Sn(2), two equivalent Sn(3), two equivalent Sn(4), two equivalent Sn(6), and four equivalent Sn(8) atoms to form distorted BaSn12 cuboctahedra that share corners with two equivalent Ba(3)Sn12 cuboctahedra, corners with four equivalent Ba(2)Sn12 cuboctahedra, faces with two equivalent Ba(3)Sn12 cuboctahedra, faces with two equivalent Sr(1)Sn12 cuboctahedra, and faces with four equivalent Ba(1)Sn12 cuboctahedra. Sr(1) is bonded to two equivalent Sn(1), two equivalent Sn(5), two equivalent Sn(7), two equivalent Sn(8), and four equivalent Sn(3) atoms to form distorted SrSn12 cuboctahedra that share corners with two equivalent Sr(1)Sn12 cuboctahedra, corners with four equivalent Ba(1)Sn12 cuboctahedra, faces with two equivalent Ba(3)Sn12 cuboctahedra, faces with two equivalent Sr(1)Sn12 cuboctahedra, and faces with four equivalent Ba(2)Sn12 cuboctahedra. There are eight inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 10-coordinate geometry to two equivalent Ba(2), two equivalent Sr(1), two equivalent Sn(4), and four equivalent Sn(7) atoms. In the second Sn site, Sn(2) is bonded in a 10-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), two equivalent Sn(3), and four equivalent Sn(8) atoms. In the third Sn site, Sn(3) is bonded in a 10-coordinate geometry to one Ba(2), one Ba(3), two equivalent Sr(1), one Sn(2), one Sn(3), two equivalent Sn(5), and two equivalent Sn(8) atoms. In the fourth Sn site, Sn(4) is bonded in a 10-coordinate geometry to one Ba(2), one Ba(3), two equivalent Ba(1), one Sn(1), one Sn(4), two equivalent Sn(6), and two equivalent Sn(7) atoms. In the fifth Sn site, Sn(5) is bonded in a 10-coordinate geometry to two equivalent Ba(2), two equivalent Sr(1), two equivalent Sn(8), and four equivalent Sn(3) atoms. In the sixth Sn site, Sn(6) is bonded in a 10-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), two equivalent Sn(7), and four equivalent Sn(4) atoms. In the seventh Sn site, Sn(7) is bonded in a 10-coordinate geometry to one Ba(1), two equivalent Ba(2), one Sr(1), one Sn(6), one Sn(7), two equivalent Sn(1), and two equivalent Sn(4) atoms. In the eighth Sn site, Sn(8) is bonded in a 10-coordinate geometry to one Ba(1), two equivalent Ba(3), one Sr(1), one Sn(5), one Sn(8), two equivalent Sn(2), and two equivalent Sn(3) atoms. is represented by the CIF file [CIF]
data_Ba3SrSn12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.341
_cell_length_b   7.354
_cell_length_c   12.980
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   509.857
_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
  Ba  Ba0  1  0.000  0.000  0.667  1.0
  Ba  Ba1  1  0.500  0.000  0.333  1.0
  Ba  Ba2  1  0.500  0.500  0.834  1.0
  Sr  Sr3  1  0.000  0.500  0.167  1.0
  Sn  Sn4  1  0.500  0.500  0.354  1.0
  Sn  Sn5  1  0.500  0.000  0.859  1.0
  Sn  Sn6  1  0.500  0.782  0.073  1.0
  Sn  Sn7  1  0.500  0.288  0.570  1.0
  Sn  Sn8  1  0.500  0.218  0.073  1.0
  Sn  Sn9  1  0.500  0.712  0.570  1.0
  Sn  Sn10  1  0.000  0.000  0.143  1.0
  Sn  Sn11  1  0.000  0.500  0.642  1.0
  Sn  Sn12  1  0.000  0.712  0.428  1.0
  Sn  Sn13  1  0.000  0.214  0.930  1.0
  Sn  Sn14  1  0.000  0.288  0.428  1.0
  Sn  Sn15  1  0.000  0.786  0.930  1.0
[/CIF]
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