The crystal structure described by Er2AlGe4 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 10-coordinate geometry to two equivalent Ge(1), two equivalent Ge(3), two equivalent Ge(4), and four equivalent Ge(2) atoms. In the second Er site, Er(2) is bonded in a 14-coordinate geometry to four equivalent Al(1), two equivalent Ge(2), two equivalent Ge(3), two equivalent Ge(4), and four equivalent Ge(1) atoms. Al(1) is bonded in a 5-coordinate geometry to four equivalent Er(2), one Ge(1), two equivalent Ge(3), and two equivalent Ge(4) atoms. There are four inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one Al(1), and two equivalent Ge(2) atoms. In the second Ge site, Ge(2) is bonded in a 8-coordinate geometry to two equivalent Er(2), four equivalent Er(1), and two equivalent Ge(1) atoms. In the third Ge site, Ge(3) is bonded in a 10-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Al(1), and four equivalent Ge(4) atoms. In the fourth Ge site, Ge(4) is bonded in a 4-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Al(1), and four equivalent Ge(3) atoms. is represented by the CIF card [CIF]
data_Er2AlGe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.132
_cell_length_b   4.221
_cell_length_c   8.600
_cell_angle_alpha   75.795
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   145.408
_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
  Er  Er0  1  0.250  0.901  0.198  1.0
  Er  Er1  1  0.750  0.103  0.794  1.0
  Al  Al2  1  0.250  0.680  0.639  1.0
  Ge  Ge3  1  0.250  0.536  0.928  1.0
  Ge  Ge4  1  0.750  0.445  0.110  1.0
  Ge  Ge5  1  0.250  0.265  0.469  1.0
  Ge  Ge6  1  0.750  0.766  0.467  1.0
[/CIF]
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The crystal structure described by Er2AlGe4 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 10-coordinate geometry to two equivalent Ge(1), two equivalent Ge(3), two equivalent Ge(4), and four equivalent Ge(2) atoms. In the second Er site, Er(2) is bonded in a 14-coordinate geometry to four equivalent Al(1), two equivalent Ge(2), two equivalent Ge(3), two equivalent Ge(4), and four equivalent Ge(1) atoms. Al(1) is bonded in a 5-coordinate geometry to four equivalent Er(2), one Ge(1), two equivalent Ge(3), and two equivalent Ge(4) atoms. There are four inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one Al(1), and two equivalent Ge(2) atoms. In the second Ge site, Ge(2) is bonded in a 8-coordinate geometry to two equivalent Er(2), four equivalent Er(1), and two equivalent Ge(1) atoms. In the third Ge site, Ge(3) is bonded in a 10-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Al(1), and four equivalent Ge(4) atoms. In the fourth Ge site, Ge(4) is bonded in a 4-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Al(1), and four equivalent Ge(3) atoms. is represented by the CIF card [CIF]
data_Er2AlGe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.132
_cell_length_b   4.221
_cell_length_c   8.600
_cell_angle_alpha   75.795
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   145.408
_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
  Er  Er0  1  0.250  0.901  0.198  1.0
  Er  Er1  1  0.750  0.103  0.794  1.0
  Al  Al2  1  0.250  0.680  0.639  1.0
  Ge  Ge3  1  0.250  0.536  0.928  1.0
  Ge  Ge4  1  0.750  0.445  0.110  1.0
  Ge  Ge5  1  0.250  0.265  0.469  1.0
  Ge  Ge6  1  0.750  0.766  0.467  1.0
[/CIF]
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