The structure described by Ca4Al3Mg crystallizes in the orthorhombic Pbcm space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to one Al(2), three equivalent Al(3), and four equivalent Al(1) atoms. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the third Ca site, Ca(3) is bonded in a 6-coordinate geometry to two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the fourth Ca site, Ca(4) is bonded in a 4-coordinate geometry to one Al(3) and three equivalent Al(2) atoms. Mg(1) is bonded in a distorted linear geometry to two equivalent Al(2) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Ca(2), two equivalent Ca(3), four equivalent Ca(1), two equivalent Al(1), and two equivalent Al(3) atoms to form a mixture of distorted face, corner, and edge-sharing AlCa8Al4 cuboctahedra. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to one Ca(1), two equivalent Ca(2), two equivalent Ca(3), three equivalent Ca(4), and two equivalent Mg(1) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Ca(4), two equivalent Ca(2), two equivalent Ca(3), three equivalent Ca(1), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca4MgAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.856
_cell_length_b   6.175
_cell_length_c   24.253
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   877.079
_cell_formula_units_Z   4
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  0.750  0.686  0.290  1.0
  Ca  Ca1  1  0.250  0.314  0.710  1.0
  Ca  Ca2  1  0.250  0.243  0.124  1.0
  Ca  Ca3  1  0.250  0.920  0.357  1.0
  Ca  Ca4  1  0.750  0.243  0.376  1.0
  Ca  Ca5  1  0.250  0.080  0.857  1.0
  Ca  Ca6  1  0.250  0.503  0.954  1.0
  Ca  Ca7  1  0.750  0.503  0.546  1.0
  Ca  Ca8  1  0.750  0.080  0.643  1.0
  Ca  Ca9  1  0.750  0.497  0.046  1.0
  Ca  Ca10  1  0.250  0.686  0.210  1.0
  Ca  Ca11  1  0.250  0.497  0.454  1.0
  Ca  Ca12  1  0.250  0.757  0.624  1.0
  Ca  Ca13  1  0.750  0.314  0.790  1.0
  Ca  Ca14  1  0.750  0.920  0.143  1.0
  Ca  Ca15  1  0.750  0.757  0.876  1.0
  Mg  Mg16  1  0.000  0.000  0.000  1.0
  Mg  Mg17  1  0.500  0.000  0.000  1.0
  Mg  Mg18  1  0.500  0.000  0.500  1.0
  Mg  Mg19  1  0.000  0.000  0.500  1.0
  Al  Al20  1  0.000  0.831  0.750  1.0
  Al  Al21  1  0.750  0.254  0.925  1.0
  Al  Al22  1  0.250  0.746  0.075  1.0
  Al  Al23  1  0.750  0.746  0.425  1.0
  Al  Al24  1  0.000  0.169  0.250  1.0
  Al  Al25  1  0.500  0.169  0.250  1.0
  Al  Al26  1  0.500  0.831  0.750  1.0
  Al  Al27  1  0.250  0.588  0.823  1.0
  Al  Al28  1  0.750  0.588  0.677  1.0
  Al  Al29  1  0.250  0.412  0.323  1.0
  Al  Al30  1  0.750  0.412  0.177  1.0
  Al  Al31  1  0.250  0.254  0.575  1.0
[/CIF]
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The structure described by Ca4Al3Mg crystallizes in the orthorhombic Pbcm space group. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 6-coordinate geometry to one Al(2), three equivalent Al(3), and four equivalent Al(1) atoms. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the third Ca site, Ca(3) is bonded in a 6-coordinate geometry to two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the fourth Ca site, Ca(4) is bonded in a 4-coordinate geometry to one Al(3) and three equivalent Al(2) atoms. Mg(1) is bonded in a distorted linear geometry to two equivalent Al(2) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Ca(2), two equivalent Ca(3), four equivalent Ca(1), two equivalent Al(1), and two equivalent Al(3) atoms to form a mixture of distorted face, corner, and edge-sharing AlCa8Al4 cuboctahedra. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to one Ca(1), two equivalent Ca(2), two equivalent Ca(3), three equivalent Ca(4), and two equivalent Mg(1) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Ca(4), two equivalent Ca(2), two equivalent Ca(3), three equivalent Ca(1), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca4MgAl3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.856
_cell_length_b   6.175
_cell_length_c   24.253
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   877.079
_cell_formula_units_Z   4
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  0.750  0.686  0.290  1.0
  Ca  Ca1  1  0.250  0.314  0.710  1.0
  Ca  Ca2  1  0.250  0.243  0.124  1.0
  Ca  Ca3  1  0.250  0.920  0.357  1.0
  Ca  Ca4  1  0.750  0.243  0.376  1.0
  Ca  Ca5  1  0.250  0.080  0.857  1.0
  Ca  Ca6  1  0.250  0.503  0.954  1.0
  Ca  Ca7  1  0.750  0.503  0.546  1.0
  Ca  Ca8  1  0.750  0.080  0.643  1.0
  Ca  Ca9  1  0.750  0.497  0.046  1.0
  Ca  Ca10  1  0.250  0.686  0.210  1.0
  Ca  Ca11  1  0.250  0.497  0.454  1.0
  Ca  Ca12  1  0.250  0.757  0.624  1.0
  Ca  Ca13  1  0.750  0.314  0.790  1.0
  Ca  Ca14  1  0.750  0.920  0.143  1.0
  Ca  Ca15  1  0.750  0.757  0.876  1.0
  Mg  Mg16  1  0.000  0.000  0.000  1.0
  Mg  Mg17  1  0.500  0.000  0.000  1.0
  Mg  Mg18  1  0.500  0.000  0.500  1.0
  Mg  Mg19  1  0.000  0.000  0.500  1.0
  Al  Al20  1  0.000  0.831  0.750  1.0
  Al  Al21  1  0.750  0.254  0.925  1.0
  Al  Al22  1  0.250  0.746  0.075  1.0
  Al  Al23  1  0.750  0.746  0.425  1.0
  Al  Al24  1  0.000  0.169  0.250  1.0
  Al  Al25  1  0.500  0.169  0.250  1.0
  Al  Al26  1  0.500  0.831  0.750  1.0
  Al  Al27  1  0.250  0.588  0.823  1.0
  Al  Al28  1  0.750  0.588  0.677  1.0
  Al  Al29  1  0.250  0.412  0.323  1.0
  Al  Al30  1  0.750  0.412  0.177  1.0
  Al  Al31  1  0.250  0.254  0.575  1.0
[/CIF]
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