The material structure described by MgCa crystallizes in the monoclinic Cm space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent Ca(3), three equivalent Ca(2), one Mg(3), two equivalent Mg(1), and two equivalent Mg(2) atoms to form distorted CaCa5Mg5 cuboctahedra that share corners with four equivalent Ca(1)Ca5Mg5 cuboctahedra, corners with eight equivalent Ca(3)Ca5Mg7 cuboctahedra,  an edgeedge with one Ca(3)Ca5Mg7 cuboctahedra, faces with two equivalent Ca(1)Ca5Mg5 cuboctahedra, and faces with three equivalent Ca(3)Ca5Mg7 cuboctahedra. In the second Ca site, Ca(2) is bonded in a 12-coordinate geometry to one Ca(3), two equivalent Ca(2), three equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), and two equivalent Mg(3) atoms. In the third Ca site, Ca(3) is bonded to one Ca(2), two equivalent Ca(1), two equivalent Ca(3), two equivalent Mg(2), two equivalent Mg(3), and three equivalent Mg(1) atoms to form distorted CaCa5Mg7 cuboctahedra that share corners with six equivalent Ca(3)Ca5Mg7 cuboctahedra, corners with eight equivalent Ca(1)Ca5Mg5 cuboctahedra,  an edgeedge with one Ca(1)Ca5Mg5 cuboctahedra, faces with two equivalent Ca(3)Ca5Mg7 cuboctahedra, and faces with three equivalent Ca(1)Ca5Mg5 cuboctahedra. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), three equivalent Ca(3), one Mg(2), and two equivalent Mg(3) atoms. In the second Mg site, Mg(2) is bonded in a 9-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), two equivalent Ca(3), one Mg(1), and two equivalent Mg(3) atoms. In the third Mg site, Mg(3) is bonded in a 9-coordinate geometry to one Ca(1), two equivalent Ca(2), two equivalent Ca(3), two equivalent Mg(1), and two equivalent Mg(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaMg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.094
_cell_length_b   7.094
_cell_length_c   8.051
_cell_angle_alpha   75.788
_cell_angle_beta   75.788
_cell_angle_gamma   29.262
_symmetry_Int_Tables_number   1
_cell_volume   191.570
_cell_formula_units_Z   3
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  0.603  0.603  0.276  1.0
  Ca  Ca1  1  0.334  0.334  0.360  1.0
  Ca  Ca2  1  0.288  0.288  0.912  1.0
  Mg  Mg3  1  1.000  1.000  0.991  1.0
  Mg  Mg4  1  0.959  0.959  0.616  1.0
  Mg  Mg5  1  0.649  0.649  0.678  1.0
[/CIF]
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The material structure described by MgCa crystallizes in the monoclinic Cm space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent Ca(3), three equivalent Ca(2), one Mg(3), two equivalent Mg(1), and two equivalent Mg(2) atoms to form distorted CaCa5Mg5 cuboctahedra that share corners with four equivalent Ca(1)Ca5Mg5 cuboctahedra, corners with eight equivalent Ca(3)Ca5Mg7 cuboctahedra,  an edgeedge with one Ca(3)Ca5Mg7 cuboctahedra, faces with two equivalent Ca(1)Ca5Mg5 cuboctahedra, and faces with three equivalent Ca(3)Ca5Mg7 cuboctahedra. In the second Ca site, Ca(2) is bonded in a 12-coordinate geometry to one Ca(3), two equivalent Ca(2), three equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), and two equivalent Mg(3) atoms. In the third Ca site, Ca(3) is bonded to one Ca(2), two equivalent Ca(1), two equivalent Ca(3), two equivalent Mg(2), two equivalent Mg(3), and three equivalent Mg(1) atoms to form distorted CaCa5Mg7 cuboctahedra that share corners with six equivalent Ca(3)Ca5Mg7 cuboctahedra, corners with eight equivalent Ca(1)Ca5Mg5 cuboctahedra,  an edgeedge with one Ca(1)Ca5Mg5 cuboctahedra, faces with two equivalent Ca(3)Ca5Mg7 cuboctahedra, and faces with three equivalent Ca(1)Ca5Mg5 cuboctahedra. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), three equivalent Ca(3), one Mg(2), and two equivalent Mg(3) atoms. In the second Mg site, Mg(2) is bonded in a 9-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), two equivalent Ca(3), one Mg(1), and two equivalent Mg(3) atoms. In the third Mg site, Mg(3) is bonded in a 9-coordinate geometry to one Ca(1), two equivalent Ca(2), two equivalent Ca(3), two equivalent Mg(1), and two equivalent Mg(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaMg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.094
_cell_length_b   7.094
_cell_length_c   8.051
_cell_angle_alpha   75.788
_cell_angle_beta   75.788
_cell_angle_gamma   29.262
_symmetry_Int_Tables_number   1
_cell_volume   191.570
_cell_formula_units_Z   3
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  0.603  0.603  0.276  1.0
  Ca  Ca1  1  0.334  0.334  0.360  1.0
  Ca  Ca2  1  0.288  0.288  0.912  1.0
  Mg  Mg3  1  1.000  1.000  0.991  1.0
  Mg  Mg4  1  0.959  0.959  0.616  1.0
  Mg  Mg5  1  0.649  0.649  0.678  1.0
[/CIF]
.