The compound described by Mg3Ca is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. Ca(1) is bonded in a distorted body-centered cubic geometry to six equivalent Mg(1) and eight equivalent Mg(2) atoms. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 14-coordinate geometry to six equivalent Ca(1) and eight equivalent Mg(2) atoms. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to four equivalent Ca(1) and four equivalent Mg(1) atoms. is represented by the CIF file [CIF]
data_CaMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.260
_cell_length_b   5.260
_cell_length_c   5.260
_cell_angle_alpha   119.880
_cell_angle_beta   119.880
_cell_angle_gamma   90.208
_symmetry_Int_Tables_number   1
_cell_volume   103.091
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.500  0.500  0.000  1.0
  Mg  Mg2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.750  0.250  0.500  1.0
[/CIF]
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The compound described by Mg3Ca is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. Ca(1) is bonded in a distorted body-centered cubic geometry to six equivalent Mg(1) and eight equivalent Mg(2) atoms. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 14-coordinate geometry to six equivalent Ca(1) and eight equivalent Mg(2) atoms. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to four equivalent Ca(1) and four equivalent Mg(1) atoms. is represented by the CIF file [CIF]
data_CaMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.260
_cell_length_b   5.260
_cell_length_c   5.260
_cell_angle_alpha   119.880
_cell_angle_beta   119.880
_cell_angle_gamma   90.208
_symmetry_Int_Tables_number   1
_cell_volume   103.091
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.500  0.500  0.000  1.0
  Mg  Mg2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.750  0.250  0.500  1.0
[/CIF]
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