The material structure described by Mg2Ca crystallizes in the monoclinic C2/c space group. Ca(1) is bonded to two equivalent Ca(1) and ten equivalent Mg(1) atoms to form CaCa2Mg10 cuboctahedra that share corners with six equivalent Ca(1)Ca2Mg10 cuboctahedra, corners with twelve equivalent Mg(1)Ca5Mg7 cuboctahedra, edges with eight equivalent Mg(1)Ca5Mg7 cuboctahedra, edges with ten equivalent Ca(1)Ca2Mg10 cuboctahedra, faces with four equivalent Ca(1)Ca2Mg10 cuboctahedra, and faces with sixteen equivalent Mg(1)Ca5Mg7 cuboctahedra. Mg(1) is bonded to five equivalent Ca(1) and seven equivalent Mg(1) atoms to form distorted MgCa5Mg7 cuboctahedra that share corners with six equivalent Ca(1)Ca2Mg10 cuboctahedra, corners with twelve equivalent Mg(1)Ca5Mg7 cuboctahedra, edges with four equivalent Ca(1)Ca2Mg10 cuboctahedra, edges with fourteen equivalent Mg(1)Ca5Mg7 cuboctahedra, faces with eight equivalent Ca(1)Ca2Mg10 cuboctahedra, and faces with twelve equivalent Mg(1)Ca5Mg7 cuboctahedra. is represented by the CIF file [CIF]
data_CaMg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.907
_cell_length_b   5.907
_cell_length_c   6.475
_cell_angle_alpha   64.962
_cell_angle_beta   64.962
_cell_angle_gamma   60.010
_symmetry_Int_Tables_number   1
_cell_volume   170.729
_cell_formula_units_Z   2
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  0.091  0.909  0.250  1.0
  Ca  Ca1  1  0.909  0.091  0.750  1.0
  Mg  Mg2  1  0.254  0.417  0.749  1.0
  Mg  Mg3  1  0.583  0.746  0.751  1.0
  Mg  Mg4  1  0.417  0.254  0.249  1.0
  Mg  Mg5  1  0.746  0.583  0.251  1.0
[/CIF]
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The material structure described by Mg2Ca crystallizes in the monoclinic C2/c space group. Ca(1) is bonded to two equivalent Ca(1) and ten equivalent Mg(1) atoms to form CaCa2Mg10 cuboctahedra that share corners with six equivalent Ca(1)Ca2Mg10 cuboctahedra, corners with twelve equivalent Mg(1)Ca5Mg7 cuboctahedra, edges with eight equivalent Mg(1)Ca5Mg7 cuboctahedra, edges with ten equivalent Ca(1)Ca2Mg10 cuboctahedra, faces with four equivalent Ca(1)Ca2Mg10 cuboctahedra, and faces with sixteen equivalent Mg(1)Ca5Mg7 cuboctahedra. Mg(1) is bonded to five equivalent Ca(1) and seven equivalent Mg(1) atoms to form distorted MgCa5Mg7 cuboctahedra that share corners with six equivalent Ca(1)Ca2Mg10 cuboctahedra, corners with twelve equivalent Mg(1)Ca5Mg7 cuboctahedra, edges with four equivalent Ca(1)Ca2Mg10 cuboctahedra, edges with fourteen equivalent Mg(1)Ca5Mg7 cuboctahedra, faces with eight equivalent Ca(1)Ca2Mg10 cuboctahedra, and faces with twelve equivalent Mg(1)Ca5Mg7 cuboctahedra. is represented by the CIF file [CIF]
data_CaMg2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.907
_cell_length_b   5.907
_cell_length_c   6.475
_cell_angle_alpha   64.962
_cell_angle_beta   64.962
_cell_angle_gamma   60.010
_symmetry_Int_Tables_number   1
_cell_volume   170.729
_cell_formula_units_Z   2
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  0.091  0.909  0.250  1.0
  Ca  Ca1  1  0.909  0.091  0.750  1.0
  Mg  Mg2  1  0.254  0.417  0.749  1.0
  Mg  Mg3  1  0.583  0.746  0.751  1.0
  Mg  Mg4  1  0.417  0.254  0.249  1.0
  Mg  Mg5  1  0.746  0.583  0.251  1.0
[/CIF]
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