The structure described by Mg2Sc crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), four equivalent Mg(2), and six equivalent Sc(1) atoms to form MgMg6Sc6 cuboctahedra that share corners with six equivalent Mg(2)Mg10Sc2 cuboctahedra, corners with six equivalent Mg(1)Mg6Sc6 cuboctahedra, corners with six equivalent Sc(1)Mg8Sc4 cuboctahedra, edges with three equivalent Mg(2)Mg10Sc2 cuboctahedra, edges with seven equivalent Sc(1)Mg8Sc4 cuboctahedra, edges with eight equivalent Mg(1)Mg6Sc6 cuboctahedra, faces with six equivalent Mg(1)Mg6Sc6 cuboctahedra, faces with six equivalent Sc(1)Mg8Sc4 cuboctahedra, and faces with eight equivalent Mg(2)Mg10Sc2 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), six equivalent Mg(2), and two equivalent Sc(1) atoms to form MgMg10Sc2 cuboctahedra that share corners with six equivalent Mg(2)Mg10Sc2 cuboctahedra, corners with six equivalent Mg(1)Mg6Sc6 cuboctahedra, corners with six equivalent Sc(1)Mg8Sc4 cuboctahedra, edges with three equivalent Mg(1)Mg6Sc6 cuboctahedra, edges with four equivalent Mg(2)Mg10Sc2 cuboctahedra, edges with eleven equivalent Sc(1)Mg8Sc4 cuboctahedra, faces with four equivalent Sc(1)Mg8Sc4 cuboctahedra, faces with eight equivalent Mg(2)Mg10Sc2 cuboctahedra, and faces with eight equivalent Mg(1)Mg6Sc6 cuboctahedra. Sc(1) is bonded to two equivalent Mg(2), six equivalent Mg(1), and four equivalent Sc(1) atoms to form ScMg8Sc4 cuboctahedra that share corners with six equivalent Mg(2)Mg10Sc2 cuboctahedra, corners with six equivalent Mg(1)Mg6Sc6 cuboctahedra, corners with six equivalent Sc(1)Mg8Sc4 cuboctahedra, edges with seven equivalent Mg(1)Mg6Sc6 cuboctahedra, edges with eleven equivalent Mg(2)Mg10Sc2 cuboctahedra, faces with four equivalent Mg(2)Mg10Sc2 cuboctahedra, faces with six equivalent Mg(1)Mg6Sc6 cuboctahedra, and faces with ten equivalent Sc(1)Mg8Sc4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Sc
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.398
_cell_length_b   8.398
_cell_length_c   5.162
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   157.548
_symmetry_Int_Tables_number   1
_cell_volume   139.015
_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
  Mg  Mg0  1  0.110  0.890  0.250  1.0
  Mg  Mg1  1  0.775  0.225  0.250  1.0
  Mg  Mg2  1  0.890  0.110  0.750  1.0
  Mg  Mg3  1  0.225  0.775  0.750  1.0
  Sc  Sc4  1  0.443  0.557  0.250  1.0
  Sc  Sc5  1  0.557  0.443  0.750  1.0
[/CIF]
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The structure described by Mg2Sc crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), four equivalent Mg(2), and six equivalent Sc(1) atoms to form MgMg6Sc6 cuboctahedra that share corners with six equivalent Mg(2)Mg10Sc2 cuboctahedra, corners with six equivalent Mg(1)Mg6Sc6 cuboctahedra, corners with six equivalent Sc(1)Mg8Sc4 cuboctahedra, edges with three equivalent Mg(2)Mg10Sc2 cuboctahedra, edges with seven equivalent Sc(1)Mg8Sc4 cuboctahedra, edges with eight equivalent Mg(1)Mg6Sc6 cuboctahedra, faces with six equivalent Mg(1)Mg6Sc6 cuboctahedra, faces with six equivalent Sc(1)Mg8Sc4 cuboctahedra, and faces with eight equivalent Mg(2)Mg10Sc2 cuboctahedra. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), six equivalent Mg(2), and two equivalent Sc(1) atoms to form MgMg10Sc2 cuboctahedra that share corners with six equivalent Mg(2)Mg10Sc2 cuboctahedra, corners with six equivalent Mg(1)Mg6Sc6 cuboctahedra, corners with six equivalent Sc(1)Mg8Sc4 cuboctahedra, edges with three equivalent Mg(1)Mg6Sc6 cuboctahedra, edges with four equivalent Mg(2)Mg10Sc2 cuboctahedra, edges with eleven equivalent Sc(1)Mg8Sc4 cuboctahedra, faces with four equivalent Sc(1)Mg8Sc4 cuboctahedra, faces with eight equivalent Mg(2)Mg10Sc2 cuboctahedra, and faces with eight equivalent Mg(1)Mg6Sc6 cuboctahedra. Sc(1) is bonded to two equivalent Mg(2), six equivalent Mg(1), and four equivalent Sc(1) atoms to form ScMg8Sc4 cuboctahedra that share corners with six equivalent Mg(2)Mg10Sc2 cuboctahedra, corners with six equivalent Mg(1)Mg6Sc6 cuboctahedra, corners with six equivalent Sc(1)Mg8Sc4 cuboctahedra, edges with seven equivalent Mg(1)Mg6Sc6 cuboctahedra, edges with eleven equivalent Mg(2)Mg10Sc2 cuboctahedra, faces with four equivalent Mg(2)Mg10Sc2 cuboctahedra, faces with six equivalent Mg(1)Mg6Sc6 cuboctahedra, and faces with ten equivalent Sc(1)Mg8Sc4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Sc
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.398
_cell_length_b   8.398
_cell_length_c   5.162
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   157.548
_symmetry_Int_Tables_number   1
_cell_volume   139.015
_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
  Mg  Mg0  1  0.110  0.890  0.250  1.0
  Mg  Mg1  1  0.775  0.225  0.250  1.0
  Mg  Mg2  1  0.890  0.110  0.750  1.0
  Mg  Mg3  1  0.225  0.775  0.750  1.0
  Sc  Sc4  1  0.443  0.557  0.250  1.0
  Sc  Sc5  1  0.557  0.443  0.750  1.0
[/CIF]
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