The material structure described by EuAl2Ge2 crystallizes in the trigonal P-3m1 space group. Eu(1) is bonded to six equivalent Ge(1) atoms to form EuGe6 octahedra that share corners with twelve equivalent Al(1)Ge4 tetrahedra, edges with six equivalent Eu(1)Ge6 octahedra, and edges with six equivalent Al(1)Ge4 tetrahedra. Al(1) is bonded to four equivalent Ge(1) atoms to form AlGe4 tetrahedra that share corners with six equivalent Eu(1)Ge6 octahedra, corners with six equivalent Al(1)Ge4 tetrahedra, edges with three equivalent Eu(1)Ge6 octahedra, and edges with three equivalent Al(1)Ge4 tetrahedra. The corner-sharing octahedral tilt angles range from 21-52°. Ge(1) is bonded to three equivalent Eu(1) and four equivalent Al(1) atoms to form a mixture of distorted corner and edge-sharing GeEu3Al4 pentagonal bipyramids. is represented by the CIF file [CIF]
data_Eu(AlGe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.218
_cell_length_b   4.218
_cell_length_c   7.196
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   110.882
_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
  Eu  Eu0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.667  0.333  0.372  1.0
  Al  Al2  1  0.333  0.667  0.628  1.0
  Ge  Ge3  1  0.667  0.333  0.733  1.0
  Ge  Ge4  1  0.333  0.667  0.267  1.0
[/CIF]
.
The material structure described by EuAl2Ge2 crystallizes in the trigonal P-3m1 space group. Eu(1) is bonded to six equivalent Ge(1) atoms to form EuGe6 octahedra that share corners with twelve equivalent Al(1)Ge4 tetrahedra, edges with six equivalent Eu(1)Ge6 octahedra, and edges with six equivalent Al(1)Ge4 tetrahedra. Al(1) is bonded to four equivalent Ge(1) atoms to form AlGe4 tetrahedra that share corners with six equivalent Eu(1)Ge6 octahedra, corners with six equivalent Al(1)Ge4 tetrahedra, edges with three equivalent Eu(1)Ge6 octahedra, and edges with three equivalent Al(1)Ge4 tetrahedra. The corner-sharing octahedral tilt angles range from 21-52°. Ge(1) is bonded to three equivalent Eu(1) and four equivalent Al(1) atoms to form a mixture of distorted corner and edge-sharing GeEu3Al4 pentagonal bipyramids. is represented by the CIF file [CIF]
data_Eu(AlGe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.218
_cell_length_b   4.218
_cell_length_c   7.196
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   110.882
_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
  Eu  Eu0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.667  0.333  0.372  1.0
  Al  Al2  1  0.333  0.667  0.628  1.0
  Ge  Ge3  1  0.667  0.333  0.733  1.0
  Ge  Ge4  1  0.333  0.667  0.267  1.0
[/CIF]
.