The compound described by Ca16Mg3Sn13 crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to one Sn(1), two equivalent Sn(5), and three equivalent Sn(3) atoms. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one Sn(2), two equivalent Sn(5), and three equivalent Sn(4) atoms. In the third Ca site, Ca(3) is bonded in a 6-coordinate geometry to one Sn(2), one Sn(3), two equivalent Sn(1), and two equivalent Sn(5) atoms. In the fourth Ca site, Ca(4) is bonded in a 6-coordinate geometry to one Sn(1), one Sn(4), two equivalent Sn(2), and two equivalent Sn(5) atoms. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to two equivalent Sn(2) and two equivalent Sn(4) atoms. In the second Mg site, Mg(2) is bonded in a distorted hexagonal planar geometry to two equivalent Sn(1), two equivalent Sn(3), and two equivalent Sn(6) atoms. In the third Mg site, Mg(3) is bonded in a 4-coordinate geometry to two equivalent Sn(2) and two equivalent Sn(4) atoms. There are six inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 10-coordinate geometry to two equivalent Ca(1), two equivalent Ca(4), four equivalent Ca(3), one Mg(2), and one Sn(6) atom. In the second Sn site, Sn(2) is bonded in a 10-coordinate geometry to two equivalent Ca(2), two equivalent Ca(3), four equivalent Ca(4), one Mg(1), and one Mg(3) atom. In the third Sn site, Sn(3) is bonded in a 10-coordinate geometry to two equivalent Ca(3), six equivalent Ca(1), one Mg(2), and one Sn(6) atom. In the fourth Sn site, Sn(4) is bonded in a 10-coordinate geometry to two equivalent Ca(4), six equivalent Ca(2), one Mg(1), and one Mg(3) atom. In the fifth Sn site, Sn(5) is bonded in a 10-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), two equivalent Ca(3), two equivalent Ca(4), and two equivalent Sn(5) atoms. In the sixth Sn site, Sn(6) is bonded in a distorted linear geometry to two equivalent Mg(2), two equivalent Sn(1), and two equivalent Sn(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca16Mg3Sn13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.255
_cell_length_b   9.255
_cell_length_c   17.530
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   141.860
_symmetry_Int_Tables_number   1
_cell_volume   927.446
_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
  Ca  Ca0  1  0.068  0.434  0.399  1.0
  Ca  Ca1  1  0.567  0.933  0.900  1.0
  Ca  Ca2  1  0.434  0.068  0.601  1.0
  Ca  Ca3  1  0.933  0.567  0.100  1.0
  Ca  Ca4  1  0.850  0.650  0.683  1.0
  Ca  Ca5  1  0.350  0.149  0.182  1.0
  Ca  Ca6  1  0.650  0.850  0.317  1.0
  Ca  Ca7  1  0.149  0.350  0.818  1.0
  Ca  Ca8  1  0.650  0.850  0.683  1.0
  Ca  Ca9  1  0.149  0.350  0.182  1.0
  Ca  Ca10  1  0.850  0.650  0.317  1.0
  Ca  Ca11  1  0.350  0.149  0.818  1.0
  Ca  Ca12  1  0.434  0.068  0.399  1.0
  Ca  Ca13  1  0.933  0.567  0.900  1.0
  Ca  Ca14  1  0.068  0.434  0.601  1.0
  Ca  Ca15  1  0.567  0.933  0.100  1.0
  Mg  Mg16  1  0.500  0.500  0.000  1.0
  Mg  Mg17  1  0.499  0.499  0.500  1.0
  Mg  Mg18  1  1.000  1.000  0.000  1.0
  Sn  Sn19  1  0.252  0.252  0.653  1.0
  Sn  Sn20  1  0.749  0.749  0.154  1.0
  Sn  Sn21  1  0.252  0.252  0.347  1.0
  Sn  Sn22  1  0.749  0.749  0.846  1.0
  Sn  Sn23  1  0.595  0.903  0.500  1.0
  Sn  Sn24  1  0.097  0.402  0.000  1.0
  Sn  Sn25  1  0.903  0.595  0.500  1.0
  Sn  Sn26  1  0.402  0.097  0.000  1.0
  Sn  Sn27  1  0.250  0.750  0.750  1.0
  Sn  Sn28  1  0.750  0.250  0.250  1.0
  Sn  Sn29  1  0.750  0.250  0.750  1.0
  Sn  Sn30  1  0.250  0.750  0.250  1.0
  Sn  Sn31  1  0.001  0.001  0.500  1.0
[/CIF]
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The compound described by Ca16Mg3Sn13 crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to one Sn(1), two equivalent Sn(5), and three equivalent Sn(3) atoms. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one Sn(2), two equivalent Sn(5), and three equivalent Sn(4) atoms. In the third Ca site, Ca(3) is bonded in a 6-coordinate geometry to one Sn(2), one Sn(3), two equivalent Sn(1), and two equivalent Sn(5) atoms. In the fourth Ca site, Ca(4) is bonded in a 6-coordinate geometry to one Sn(1), one Sn(4), two equivalent Sn(2), and two equivalent Sn(5) atoms. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to two equivalent Sn(2) and two equivalent Sn(4) atoms. In the second Mg site, Mg(2) is bonded in a distorted hexagonal planar geometry to two equivalent Sn(1), two equivalent Sn(3), and two equivalent Sn(6) atoms. In the third Mg site, Mg(3) is bonded in a 4-coordinate geometry to two equivalent Sn(2) and two equivalent Sn(4) atoms. There are six inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 10-coordinate geometry to two equivalent Ca(1), two equivalent Ca(4), four equivalent Ca(3), one Mg(2), and one Sn(6) atom. In the second Sn site, Sn(2) is bonded in a 10-coordinate geometry to two equivalent Ca(2), two equivalent Ca(3), four equivalent Ca(4), one Mg(1), and one Mg(3) atom. In the third Sn site, Sn(3) is bonded in a 10-coordinate geometry to two equivalent Ca(3), six equivalent Ca(1), one Mg(2), and one Sn(6) atom. In the fourth Sn site, Sn(4) is bonded in a 10-coordinate geometry to two equivalent Ca(4), six equivalent Ca(2), one Mg(1), and one Mg(3) atom. In the fifth Sn site, Sn(5) is bonded in a 10-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), two equivalent Ca(3), two equivalent Ca(4), and two equivalent Sn(5) atoms. In the sixth Sn site, Sn(6) is bonded in a distorted linear geometry to two equivalent Mg(2), two equivalent Sn(1), and two equivalent Sn(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca16Mg3Sn13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.255
_cell_length_b   9.255
_cell_length_c   17.530
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   141.860
_symmetry_Int_Tables_number   1
_cell_volume   927.446
_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
  Ca  Ca0  1  0.068  0.434  0.399  1.0
  Ca  Ca1  1  0.567  0.933  0.900  1.0
  Ca  Ca2  1  0.434  0.068  0.601  1.0
  Ca  Ca3  1  0.933  0.567  0.100  1.0
  Ca  Ca4  1  0.850  0.650  0.683  1.0
  Ca  Ca5  1  0.350  0.149  0.182  1.0
  Ca  Ca6  1  0.650  0.850  0.317  1.0
  Ca  Ca7  1  0.149  0.350  0.818  1.0
  Ca  Ca8  1  0.650  0.850  0.683  1.0
  Ca  Ca9  1  0.149  0.350  0.182  1.0
  Ca  Ca10  1  0.850  0.650  0.317  1.0
  Ca  Ca11  1  0.350  0.149  0.818  1.0
  Ca  Ca12  1  0.434  0.068  0.399  1.0
  Ca  Ca13  1  0.933  0.567  0.900  1.0
  Ca  Ca14  1  0.068  0.434  0.601  1.0
  Ca  Ca15  1  0.567  0.933  0.100  1.0
  Mg  Mg16  1  0.500  0.500  0.000  1.0
  Mg  Mg17  1  0.499  0.499  0.500  1.0
  Mg  Mg18  1  1.000  1.000  0.000  1.0
  Sn  Sn19  1  0.252  0.252  0.653  1.0
  Sn  Sn20  1  0.749  0.749  0.154  1.0
  Sn  Sn21  1  0.252  0.252  0.347  1.0
  Sn  Sn22  1  0.749  0.749  0.846  1.0
  Sn  Sn23  1  0.595  0.903  0.500  1.0
  Sn  Sn24  1  0.097  0.402  0.000  1.0
  Sn  Sn25  1  0.903  0.595  0.500  1.0
  Sn  Sn26  1  0.402  0.097  0.000  1.0
  Sn  Sn27  1  0.250  0.750  0.750  1.0
  Sn  Sn28  1  0.750  0.250  0.250  1.0
  Sn  Sn29  1  0.750  0.250  0.750  1.0
  Sn  Sn30  1  0.250  0.750  0.250  1.0
  Sn  Sn31  1  0.001  0.001  0.500  1.0
[/CIF]
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