The compound described by YAlMgGe2 crystallizes in the trigonal P3m1 space group. Mg(1) is bonded to one Ge(2) and three equivalent Ge(1) atoms to form distorted MgGe4 tetrahedra that share corners with six equivalent Y(1)Ge6 octahedra, corners with six equivalent Mg(1)Ge4 tetrahedra, edges with three equivalent Y(1)Ge6 octahedra, and edges with three equivalent Al(1)Ge4 tetrahedra. The corner-sharing octahedral tilt angles range from 16-56°. Y(1) is bonded to three equivalent Ge(1) and three equivalent Ge(2) atoms to form YGe6 octahedra that share corners with six equivalent Mg(1)Ge4 tetrahedra, corners with six equivalent Al(1)Ge4 tetrahedra, edges with six equivalent Y(1)Ge6 octahedra, edges with three equivalent Mg(1)Ge4 tetrahedra, and edges with three equivalent Al(1)Ge4 tetrahedra. Al(1) is bonded to one Ge(1) and three equivalent Ge(2) atoms to form distorted AlGe4 tetrahedra that share corners with six equivalent Y(1)Ge6 octahedra, corners with six equivalent Al(1)Ge4 tetrahedra, edges with three equivalent Y(1)Ge6 octahedra, and edges with three equivalent Mg(1)Ge4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-57°. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to three equivalent Mg(1), three equivalent Y(1), and one Al(1) atom to form distorted GeY3Mg3Al pentagonal bipyramids that share corners with three equivalent Ge(2)Y3MgAl3 pentagonal bipyramids, edges with six equivalent Ge(1)Y3Mg3Al pentagonal bipyramids, and edges with six equivalent Ge(2)Y3MgAl3 pentagonal bipyramids. In the second Ge site, Ge(2) is bonded to one Mg(1), three equivalent Y(1), and three equivalent Al(1) atoms to form distorted GeY3MgAl3 pentagonal bipyramids that share corners with three equivalent Ge(1)Y3Mg3Al pentagonal bipyramids, edges with six equivalent Ge(1)Y3Mg3Al pentagonal bipyramids, and edges with six equivalent Ge(2)Y3MgAl3 pentagonal bipyramids. is represented by the CIF file [CIF]
data_YMgAlGe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.310
_cell_length_b   4.313
_cell_length_c   6.883
_cell_angle_alpha   90.000
_cell_angle_beta   90.003
_cell_angle_gamma   120.021
_symmetry_Int_Tables_number   1
_cell_volume   110.784
_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
  Y  Y0  1  0.000  0.000  0.006  1.0
  Mg  Mg1  1  0.667  0.333  0.361  1.0
  Al  Al2  1  0.333  0.667  0.630  1.0
  Ge  Ge3  1  0.333  0.667  0.244  1.0
  Ge  Ge4  1  0.667  0.333  0.759  1.0
[/CIF]
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The compound described by YAlMgGe2 crystallizes in the trigonal P3m1 space group. Mg(1) is bonded to one Ge(2) and three equivalent Ge(1) atoms to form distorted MgGe4 tetrahedra that share corners with six equivalent Y(1)Ge6 octahedra, corners with six equivalent Mg(1)Ge4 tetrahedra, edges with three equivalent Y(1)Ge6 octahedra, and edges with three equivalent Al(1)Ge4 tetrahedra. The corner-sharing octahedral tilt angles range from 16-56°. Y(1) is bonded to three equivalent Ge(1) and three equivalent Ge(2) atoms to form YGe6 octahedra that share corners with six equivalent Mg(1)Ge4 tetrahedra, corners with six equivalent Al(1)Ge4 tetrahedra, edges with six equivalent Y(1)Ge6 octahedra, edges with three equivalent Mg(1)Ge4 tetrahedra, and edges with three equivalent Al(1)Ge4 tetrahedra. Al(1) is bonded to one Ge(1) and three equivalent Ge(2) atoms to form distorted AlGe4 tetrahedra that share corners with six equivalent Y(1)Ge6 octahedra, corners with six equivalent Al(1)Ge4 tetrahedra, edges with three equivalent Y(1)Ge6 octahedra, and edges with three equivalent Mg(1)Ge4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-57°. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to three equivalent Mg(1), three equivalent Y(1), and one Al(1) atom to form distorted GeY3Mg3Al pentagonal bipyramids that share corners with three equivalent Ge(2)Y3MgAl3 pentagonal bipyramids, edges with six equivalent Ge(1)Y3Mg3Al pentagonal bipyramids, and edges with six equivalent Ge(2)Y3MgAl3 pentagonal bipyramids. In the second Ge site, Ge(2) is bonded to one Mg(1), three equivalent Y(1), and three equivalent Al(1) atoms to form distorted GeY3MgAl3 pentagonal bipyramids that share corners with three equivalent Ge(1)Y3Mg3Al pentagonal bipyramids, edges with six equivalent Ge(1)Y3Mg3Al pentagonal bipyramids, and edges with six equivalent Ge(2)Y3MgAl3 pentagonal bipyramids. is represented by the CIF file [CIF]
data_YMgAlGe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.310
_cell_length_b   4.313
_cell_length_c   6.883
_cell_angle_alpha   90.000
_cell_angle_beta   90.003
_cell_angle_gamma   120.021
_symmetry_Int_Tables_number   1
_cell_volume   110.784
_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
  Y  Y0  1  0.000  0.000  0.006  1.0
  Mg  Mg1  1  0.667  0.333  0.361  1.0
  Al  Al2  1  0.333  0.667  0.630  1.0
  Ge  Ge3  1  0.333  0.667  0.244  1.0
  Ge  Ge4  1  0.667  0.333  0.759  1.0
[/CIF]
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