The structure described by ErAlGeO5 crystallizes in the orthorhombic Pbam space group. Er(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form AlO6 octahedra that share corners with four equivalent Ge(1)O5 square pyramids and edges with two equivalent Al(1)O6 octahedra. Ge(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted GeO5 square pyramids that share corners with four equivalent Al(1)O6 octahedra and  an edgeedge with one Ge(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 49-52°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Er(1), one Al(1), and one Ge(1) atom to form distorted OEr2AlGe tetrahedra that share corners with four equivalent O(3)Er2Ge2 tetrahedra, corners with six equivalent O(1)Er2AlGe tetrahedra, corners with two equivalent O(2)Er2Al2 trigonal pyramids,  an edgeedge with one O(1)Er2AlGe tetrahedra,  an edgeedge with one O(3)Er2Ge2 tetrahedra, and edges with two equivalent O(2)Er2Al2 trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Er(1) and two equivalent Al(1) atoms to form distorted OEr2Al2 trigonal pyramids that share corners with four equivalent O(1)Er2AlGe tetrahedra, corners with four equivalent O(3)Er2Ge2 tetrahedra, corners with two equivalent O(2)Er2Al2 trigonal pyramids, edges with four equivalent O(1)Er2AlGe tetrahedra, and  an edgeedge with one O(2)Er2Al2 trigonal pyramid. In the third O site, O(3) is bonded to two equivalent Er(1) and two equivalent Ge(1) atoms to form distorted OEr2Ge2 tetrahedra that share corners with eight equivalent O(1)Er2AlGe tetrahedra, corners with four equivalent O(2)Er2Al2 trigonal pyramids, edges with two equivalent O(1)Er2AlGe tetrahedra, and edges with two equivalent O(3)Er2Ge2 tetrahedra. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Al(1) and one Ge(1) atom. is represented by the CIF card [CIF]
data_ErAlGeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.652
_cell_length_b   7.281
_cell_length_c   8.383
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   345.001
_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
  Er  Er0  1  0.500  0.357  0.326  1.0
  Er  Er1  1  0.500  0.643  0.674  1.0
  Er  Er2  1  0.500  0.143  0.826  1.0
  Er  Er3  1  0.500  0.857  0.174  1.0
  Al  Al4  1  0.252  0.000  0.500  1.0
  Al  Al5  1  0.748  0.000  0.500  1.0
  Al  Al6  1  0.748  0.500  0.000  1.0
  Al  Al7  1  0.252  0.500  0.000  1.0
  Ge  Ge8  1  0.000  0.121  0.145  1.0
  Ge  Ge9  1  0.000  0.879  0.855  1.0
  Ge  Ge10  1  0.000  0.379  0.645  1.0
  Ge  Ge11  1  0.000  0.621  0.355  1.0
  O  O12  1  0.249  0.107  0.287  1.0
  O  O13  1  0.751  0.893  0.713  1.0
  O  O14  1  0.249  0.893  0.713  1.0
  O  O15  1  0.751  0.393  0.787  1.0
  O  O16  1  0.751  0.107  0.287  1.0
  O  O17  1  0.249  0.607  0.213  1.0
  O  O18  1  0.751  0.607  0.213  1.0
  O  O19  1  0.249  0.393  0.787  1.0
  O  O20  1  0.500  0.338  0.055  1.0
  O  O21  1  0.500  0.662  0.945  1.0
  O  O22  1  0.500  0.162  0.555  1.0
  O  O23  1  0.500  0.838  0.445  1.0
  O  O24  1  0.217  0.000  0.000  1.0
  O  O25  1  0.783  0.000  0.000  1.0
  O  O26  1  0.783  0.500  0.500  1.0
  O  O27  1  0.217  0.500  0.500  1.0
  O  O28  1  0.000  0.347  0.068  1.0
  O  O29  1  0.000  0.653  0.932  1.0
  O  O30  1  0.000  0.153  0.568  1.0
  O  O31  1  0.000  0.847  0.432  1.0
[/CIF]
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The structure described by ErAlGeO5 crystallizes in the orthorhombic Pbam space group. Er(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form AlO6 octahedra that share corners with four equivalent Ge(1)O5 square pyramids and edges with two equivalent Al(1)O6 octahedra. Ge(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted GeO5 square pyramids that share corners with four equivalent Al(1)O6 octahedra and  an edgeedge with one Ge(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 49-52°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Er(1), one Al(1), and one Ge(1) atom to form distorted OEr2AlGe tetrahedra that share corners with four equivalent O(3)Er2Ge2 tetrahedra, corners with six equivalent O(1)Er2AlGe tetrahedra, corners with two equivalent O(2)Er2Al2 trigonal pyramids,  an edgeedge with one O(1)Er2AlGe tetrahedra,  an edgeedge with one O(3)Er2Ge2 tetrahedra, and edges with two equivalent O(2)Er2Al2 trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Er(1) and two equivalent Al(1) atoms to form distorted OEr2Al2 trigonal pyramids that share corners with four equivalent O(1)Er2AlGe tetrahedra, corners with four equivalent O(3)Er2Ge2 tetrahedra, corners with two equivalent O(2)Er2Al2 trigonal pyramids, edges with four equivalent O(1)Er2AlGe tetrahedra, and  an edgeedge with one O(2)Er2Al2 trigonal pyramid. In the third O site, O(3) is bonded to two equivalent Er(1) and two equivalent Ge(1) atoms to form distorted OEr2Ge2 tetrahedra that share corners with eight equivalent O(1)Er2AlGe tetrahedra, corners with four equivalent O(2)Er2Al2 trigonal pyramids, edges with two equivalent O(1)Er2AlGe tetrahedra, and edges with two equivalent O(3)Er2Ge2 tetrahedra. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Al(1) and one Ge(1) atom. is represented by the CIF card [CIF]
data_ErAlGeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.652
_cell_length_b   7.281
_cell_length_c   8.383
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   345.001
_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
  Er  Er0  1  0.500  0.357  0.326  1.0
  Er  Er1  1  0.500  0.643  0.674  1.0
  Er  Er2  1  0.500  0.143  0.826  1.0
  Er  Er3  1  0.500  0.857  0.174  1.0
  Al  Al4  1  0.252  0.000  0.500  1.0
  Al  Al5  1  0.748  0.000  0.500  1.0
  Al  Al6  1  0.748  0.500  0.000  1.0
  Al  Al7  1  0.252  0.500  0.000  1.0
  Ge  Ge8  1  0.000  0.121  0.145  1.0
  Ge  Ge9  1  0.000  0.879  0.855  1.0
  Ge  Ge10  1  0.000  0.379  0.645  1.0
  Ge  Ge11  1  0.000  0.621  0.355  1.0
  O  O12  1  0.249  0.107  0.287  1.0
  O  O13  1  0.751  0.893  0.713  1.0
  O  O14  1  0.249  0.893  0.713  1.0
  O  O15  1  0.751  0.393  0.787  1.0
  O  O16  1  0.751  0.107  0.287  1.0
  O  O17  1  0.249  0.607  0.213  1.0
  O  O18  1  0.751  0.607  0.213  1.0
  O  O19  1  0.249  0.393  0.787  1.0
  O  O20  1  0.500  0.338  0.055  1.0
  O  O21  1  0.500  0.662  0.945  1.0
  O  O22  1  0.500  0.162  0.555  1.0
  O  O23  1  0.500  0.838  0.445  1.0
  O  O24  1  0.217  0.000  0.000  1.0
  O  O25  1  0.783  0.000  0.000  1.0
  O  O26  1  0.783  0.500  0.500  1.0
  O  O27  1  0.217  0.500  0.500  1.0
  O  O28  1  0.000  0.347  0.068  1.0
  O  O29  1  0.000  0.653  0.932  1.0
  O  O30  1  0.000  0.153  0.568  1.0
  O  O31  1  0.000  0.847  0.432  1.0
[/CIF]
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