The structure described by Pa2Er2O5 crystallizes in the tetragonal P4/mmm space group. Pa(1) is bonded in a distorted pentagonal planar geometry to four equivalent Er(1), one O(2), and four equivalent O(1) atoms. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to eight equivalent Pa(1) and four equivalent Er(1) atoms to form distorted ErEr4Pa8 cuboctahedra that share corners with four equivalent Er(1)Er4Pa8 cuboctahedra, corners with sixteen equivalent O(1)Er2Pa2 tetrahedra, edges with eight equivalent O(1)Er2Pa2 tetrahedra, and faces with eight equivalent Er(1)Er4Pa8 cuboctahedra. In the second Er site, Er(2) is bonded in a distorted body-centered cubic geometry to eight equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Pa(1) and two equivalent Er(2) atoms to form OEr2Pa2 tetrahedra that share corners with four equivalent Er(1)Er4Pa8 cuboctahedra, corners with ten equivalent O(1)Er2Pa2 tetrahedra, edges with two equivalent Er(1)Er4Pa8 cuboctahedra, and edges with five equivalent O(1)Er2Pa2 tetrahedra. In the second O site, O(2) is bonded in a linear geometry to two equivalent Pa(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2Pa2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.827
_cell_length_b   4.094
_cell_length_c   4.094
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   164.719
_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  0.000  0.000  0.000  1.0
  Er  Er1  1  0.500  0.000  0.000  1.0
  Pa  Pa2  1  0.273  0.500  0.500  1.0
  Pa  Pa3  1  0.727  0.500  0.500  1.0
  O  O4  1  0.348  0.500  0.000  1.0
  O  O5  1  0.652  0.500  0.000  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.348  0.000  0.500  1.0
  O  O8  1  0.652  0.000  0.500  1.0
[/CIF]
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The structure described by Pa2Er2O5 crystallizes in the tetragonal P4/mmm space group. Pa(1) is bonded in a distorted pentagonal planar geometry to four equivalent Er(1), one O(2), and four equivalent O(1) atoms. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to eight equivalent Pa(1) and four equivalent Er(1) atoms to form distorted ErEr4Pa8 cuboctahedra that share corners with four equivalent Er(1)Er4Pa8 cuboctahedra, corners with sixteen equivalent O(1)Er2Pa2 tetrahedra, edges with eight equivalent O(1)Er2Pa2 tetrahedra, and faces with eight equivalent Er(1)Er4Pa8 cuboctahedra. In the second Er site, Er(2) is bonded in a distorted body-centered cubic geometry to eight equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Pa(1) and two equivalent Er(2) atoms to form OEr2Pa2 tetrahedra that share corners with four equivalent Er(1)Er4Pa8 cuboctahedra, corners with ten equivalent O(1)Er2Pa2 tetrahedra, edges with two equivalent Er(1)Er4Pa8 cuboctahedra, and edges with five equivalent O(1)Er2Pa2 tetrahedra. In the second O site, O(2) is bonded in a linear geometry to two equivalent Pa(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er2Pa2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.827
_cell_length_b   4.094
_cell_length_c   4.094
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   164.719
_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  0.000  0.000  0.000  1.0
  Er  Er1  1  0.500  0.000  0.000  1.0
  Pa  Pa2  1  0.273  0.500  0.500  1.0
  Pa  Pa3  1  0.727  0.500  0.500  1.0
  O  O4  1  0.348  0.500  0.000  1.0
  O  O5  1  0.652  0.500  0.000  1.0
  O  O6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.348  0.000  0.500  1.0
  O  O8  1  0.652  0.000  0.500  1.0
[/CIF]
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