The compound described by Sr3CaSn16 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 13-coordinate geometry to one Sn(1), two equivalent Sn(3), two equivalent Sn(5), four equivalent Sn(7), and four equivalent Sn(9) atoms. In the second Sr site, Sr(2) is bonded in a 13-coordinate geometry to one Sn(1), one Sn(2), one Sn(3), one Sn(6), one Sn(7), two equivalent Sn(4), two equivalent Sn(5), two equivalent Sn(8), and two equivalent Sn(9) atoms. Ca(1) is bonded in a 13-coordinate geometry to one Sn(2), two equivalent Sn(3), two equivalent Sn(4), four equivalent Sn(6), and four equivalent Sn(8) atoms. There are nine inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 11-coordinate geometry to one Sr(1), two equivalent Sr(2), four equivalent Sn(4), and four equivalent Sn(9) atoms. In the second Sn site, Sn(2) is bonded in a 11-coordinate geometry to two equivalent Sr(2), one Ca(1), four equivalent Sn(5), and four equivalent Sn(8) atoms. In the third Sn site, Sn(3) is bonded in a 11-coordinate geometry to one Sr(1), one Sr(2), one Ca(1), two equivalent Sn(6), two equivalent Sn(7), two equivalent Sn(8), and two equivalent Sn(9) atoms. In the fourth Sn site, Sn(4) is bonded in a 9-coordinate geometry to two equivalent Sr(2), one Ca(1), one Sn(4), one Sn(9), two equivalent Sn(1), and two equivalent Sn(6) atoms. In the fifth Sn site, Sn(5) is bonded in a 9-coordinate geometry to one Sr(1), two equivalent Sr(2), one Sn(5), one Sn(8), two equivalent Sn(2), and two equivalent Sn(7) atoms. In the sixth Sn site, Sn(6) is bonded in a 9-coordinate geometry to one Sr(2), two equivalent Ca(1), one Sn(7), one Sn(8), two equivalent Sn(3), and two equivalent Sn(4) atoms. In the seventh Sn site, Sn(7) is bonded in a 9-coordinate geometry to one Sr(2), two equivalent Sr(1), one Sn(6), one Sn(9), two equivalent Sn(3), and two equivalent Sn(5) atoms. In the eighth Sn site, Sn(8) is bonded in a 4-coordinate geometry to two equivalent Sr(2), two equivalent Ca(1), one Sn(5), one Sn(6), two equivalent Sn(2), and two equivalent Sn(3) atoms. In the ninth Sn site, Sn(9) is bonded in a 4-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Sn(4), one Sn(7), two equivalent Sn(1), and two equivalent Sn(3) atoms. is represented by the CIF card [CIF]
data_Sr3CaSn16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.455
_cell_length_b   11.455
_cell_length_c   11.455
_cell_angle_alpha   156.020
_cell_angle_beta   103.853
_cell_angle_gamma   81.192
_symmetry_Int_Tables_number   1
_cell_volume   584.863
_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  0.112  0.612  0.500  1.0
  Sr  Sr1  1  0.138  0.388  0.750  1.0
  Sr  Sr2  1  0.638  0.388  0.250  1.0
  Ca  Ca3  1  0.612  0.612  0.000  1.0
  Sn  Sn4  1  0.910  0.410  0.500  1.0
  Sn  Sn5  1  0.412  0.412  0.000  1.0
  Sn  Sn6  1  0.839  0.590  0.249  1.0
  Sn  Sn7  1  0.341  0.590  0.751  1.0
  Sn  Sn8  1  0.907  0.803  0.104  1.0
  Sn  Sn9  1  0.409  0.804  0.605  1.0
  Sn  Sn10  1  0.838  0.195  0.643  1.0
  Sn  Sn11  1  0.342  0.196  0.146  1.0
  Sn  Sn12  1  0.699  0.803  0.896  1.0
  Sn  Sn13  1  0.199  0.804  0.395  1.0
  Sn  Sn14  1  0.050  0.196  0.854  1.0
  Sn  Sn15  1  0.551  0.195  0.357  1.0
  Sn  Sn16  1  0.625  0.001  0.623  1.0
  Sn  Sn17  1  0.125  1.000  0.125  1.0
  Sn  Sn18  1  0.875  1.000  0.875  1.0
  Sn  Sn19  1  0.378  0.001  0.377  1.0
[/CIF]
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The compound described by Sr3CaSn16 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 13-coordinate geometry to one Sn(1), two equivalent Sn(3), two equivalent Sn(5), four equivalent Sn(7), and four equivalent Sn(9) atoms. In the second Sr site, Sr(2) is bonded in a 13-coordinate geometry to one Sn(1), one Sn(2), one Sn(3), one Sn(6), one Sn(7), two equivalent Sn(4), two equivalent Sn(5), two equivalent Sn(8), and two equivalent Sn(9) atoms. Ca(1) is bonded in a 13-coordinate geometry to one Sn(2), two equivalent Sn(3), two equivalent Sn(4), four equivalent Sn(6), and four equivalent Sn(8) atoms. There are nine inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 11-coordinate geometry to one Sr(1), two equivalent Sr(2), four equivalent Sn(4), and four equivalent Sn(9) atoms. In the second Sn site, Sn(2) is bonded in a 11-coordinate geometry to two equivalent Sr(2), one Ca(1), four equivalent Sn(5), and four equivalent Sn(8) atoms. In the third Sn site, Sn(3) is bonded in a 11-coordinate geometry to one Sr(1), one Sr(2), one Ca(1), two equivalent Sn(6), two equivalent Sn(7), two equivalent Sn(8), and two equivalent Sn(9) atoms. In the fourth Sn site, Sn(4) is bonded in a 9-coordinate geometry to two equivalent Sr(2), one Ca(1), one Sn(4), one Sn(9), two equivalent Sn(1), and two equivalent Sn(6) atoms. In the fifth Sn site, Sn(5) is bonded in a 9-coordinate geometry to one Sr(1), two equivalent Sr(2), one Sn(5), one Sn(8), two equivalent Sn(2), and two equivalent Sn(7) atoms. In the sixth Sn site, Sn(6) is bonded in a 9-coordinate geometry to one Sr(2), two equivalent Ca(1), one Sn(7), one Sn(8), two equivalent Sn(3), and two equivalent Sn(4) atoms. In the seventh Sn site, Sn(7) is bonded in a 9-coordinate geometry to one Sr(2), two equivalent Sr(1), one Sn(6), one Sn(9), two equivalent Sn(3), and two equivalent Sn(5) atoms. In the eighth Sn site, Sn(8) is bonded in a 4-coordinate geometry to two equivalent Sr(2), two equivalent Ca(1), one Sn(5), one Sn(6), two equivalent Sn(2), and two equivalent Sn(3) atoms. In the ninth Sn site, Sn(9) is bonded in a 4-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Sn(4), one Sn(7), two equivalent Sn(1), and two equivalent Sn(3) atoms. is represented by the CIF card [CIF]
data_Sr3CaSn16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.455
_cell_length_b   11.455
_cell_length_c   11.455
_cell_angle_alpha   156.020
_cell_angle_beta   103.853
_cell_angle_gamma   81.192
_symmetry_Int_Tables_number   1
_cell_volume   584.863
_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  0.112  0.612  0.500  1.0
  Sr  Sr1  1  0.138  0.388  0.750  1.0
  Sr  Sr2  1  0.638  0.388  0.250  1.0
  Ca  Ca3  1  0.612  0.612  0.000  1.0
  Sn  Sn4  1  0.910  0.410  0.500  1.0
  Sn  Sn5  1  0.412  0.412  0.000  1.0
  Sn  Sn6  1  0.839  0.590  0.249  1.0
  Sn  Sn7  1  0.341  0.590  0.751  1.0
  Sn  Sn8  1  0.907  0.803  0.104  1.0
  Sn  Sn9  1  0.409  0.804  0.605  1.0
  Sn  Sn10  1  0.838  0.195  0.643  1.0
  Sn  Sn11  1  0.342  0.196  0.146  1.0
  Sn  Sn12  1  0.699  0.803  0.896  1.0
  Sn  Sn13  1  0.199  0.804  0.395  1.0
  Sn  Sn14  1  0.050  0.196  0.854  1.0
  Sn  Sn15  1  0.551  0.195  0.357  1.0
  Sn  Sn16  1  0.625  0.001  0.623  1.0
  Sn  Sn17  1  0.125  1.000  0.125  1.0
  Sn  Sn18  1  0.875  1.000  0.875  1.0
  Sn  Sn19  1  0.378  0.001  0.377  1.0
[/CIF]
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