The material described by U3Er2O11 is alpha bismuth trifluoride-derived structured and crystallizes in the orthorhombic Immm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(1), two equivalent O(3), two equivalent O(4), and four equivalent O(2) atoms. In the second U site, U(2) is bonded in a body-centered cubic geometry to two equivalent O(4), four equivalent O(1), and four equivalent O(2) atoms. Er(1) is bonded in a body-centered cubic geometry to two equivalent O(2) and six equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form OU4 tetrahedra that share corners with two equivalent O(4)U6 octahedra, corners with four equivalent O(3)Er3U tetrahedra, corners with four equivalent O(1)U4 tetrahedra, corners with eight equivalent O(2)ErU3 tetrahedra, edges with two equivalent O(1)U4 tetrahedra, edges with four equivalent O(2)ErU3 tetrahedra, and faces with two equivalent O(4)U6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second O site, O(2) is bonded to one U(2), two equivalent U(1), and one Er(1) atom to form OErU3 tetrahedra that share corners with three equivalent O(4)U6 octahedra, corners with four equivalent O(1)U4 tetrahedra, corners with six equivalent O(3)Er3U tetrahedra, corners with six equivalent O(2)ErU3 tetrahedra, edges with two equivalent O(3)Er3U tetrahedra, edges with two equivalent O(2)ErU3 tetrahedra, edges with two equivalent O(1)U4 tetrahedra, and  a faceface with one O(4)U6 octahedra. The corner-sharing octahedral tilt angles range from 54-56°. In the third O site, O(3) is bonded to one U(1) and three equivalent Er(1) atoms to form OEr3U tetrahedra that share corners with two equivalent O(4)U6 octahedra, corners with two equivalent O(1)U4 tetrahedra, corners with six equivalent O(2)ErU3 tetrahedra, corners with eight equivalent O(3)Er3U tetrahedra, edges with two equivalent O(2)ErU3 tetrahedra, and edges with four equivalent O(3)Er3U tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the fourth O site, O(4) is bonded to two equivalent U(2) and four equivalent U(1) atoms to form OU6 octahedra that share corners with two equivalent O(4)U6 octahedra, corners with four equivalent O(1)U4 tetrahedra, corners with eight equivalent O(3)Er3U tetrahedra, corners with twelve equivalent O(2)ErU3 tetrahedra, edges with two equivalent O(4)U6 octahedra, faces with four equivalent O(2)ErU3 tetrahedra, and faces with four equivalent O(1)U4 tetrahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_Er2U3O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.911
_cell_length_b   9.911
_cell_length_c   9.911
_cell_angle_alpha   158.033
_cell_angle_beta   148.326
_cell_angle_gamma   38.882
_symmetry_Int_Tables_number   1
_cell_volume   190.943
_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  0.703  0.703  0.000  1.0
  Er  Er1  1  0.297  0.297  0.000  1.0
  U  U2  1  0.901  0.901  0.000  1.0
  U  U3  1  0.500  0.500  0.000  1.0
  U  U4  1  0.099  0.099  0.000  1.0
  O  O5  1  0.280  0.000  0.280  1.0
  O  O6  1  0.839  0.602  0.237  1.0
  O  O7  1  0.432  0.194  0.239  1.0
  O  O8  1  0.045  0.806  0.239  1.0
  O  O9  1  0.636  0.398  0.237  1.0
  O  O10  1  0.720  0.000  0.720  1.0
  O  O11  1  0.364  0.602  0.763  1.0
  O  O12  1  0.955  0.194  0.761  1.0
  O  O13  1  0.568  0.806  0.761  1.0
  O  O14  1  0.161  0.398  0.763  1.0
  O  O15  1  0.000  0.500  0.500  1.0
[/CIF]
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The material described by U3Er2O11 is alpha bismuth trifluoride-derived structured and crystallizes in the orthorhombic Immm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(1), two equivalent O(3), two equivalent O(4), and four equivalent O(2) atoms. In the second U site, U(2) is bonded in a body-centered cubic geometry to two equivalent O(4), four equivalent O(1), and four equivalent O(2) atoms. Er(1) is bonded in a body-centered cubic geometry to two equivalent O(2) and six equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form OU4 tetrahedra that share corners with two equivalent O(4)U6 octahedra, corners with four equivalent O(3)Er3U tetrahedra, corners with four equivalent O(1)U4 tetrahedra, corners with eight equivalent O(2)ErU3 tetrahedra, edges with two equivalent O(1)U4 tetrahedra, edges with four equivalent O(2)ErU3 tetrahedra, and faces with two equivalent O(4)U6 octahedra. The corner-sharing octahedral tilt angles are 58°. In the second O site, O(2) is bonded to one U(2), two equivalent U(1), and one Er(1) atom to form OErU3 tetrahedra that share corners with three equivalent O(4)U6 octahedra, corners with four equivalent O(1)U4 tetrahedra, corners with six equivalent O(3)Er3U tetrahedra, corners with six equivalent O(2)ErU3 tetrahedra, edges with two equivalent O(3)Er3U tetrahedra, edges with two equivalent O(2)ErU3 tetrahedra, edges with two equivalent O(1)U4 tetrahedra, and  a faceface with one O(4)U6 octahedra. The corner-sharing octahedral tilt angles range from 54-56°. In the third O site, O(3) is bonded to one U(1) and three equivalent Er(1) atoms to form OEr3U tetrahedra that share corners with two equivalent O(4)U6 octahedra, corners with two equivalent O(1)U4 tetrahedra, corners with six equivalent O(2)ErU3 tetrahedra, corners with eight equivalent O(3)Er3U tetrahedra, edges with two equivalent O(2)ErU3 tetrahedra, and edges with four equivalent O(3)Er3U tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the fourth O site, O(4) is bonded to two equivalent U(2) and four equivalent U(1) atoms to form OU6 octahedra that share corners with two equivalent O(4)U6 octahedra, corners with four equivalent O(1)U4 tetrahedra, corners with eight equivalent O(3)Er3U tetrahedra, corners with twelve equivalent O(2)ErU3 tetrahedra, edges with two equivalent O(4)U6 octahedra, faces with four equivalent O(2)ErU3 tetrahedra, and faces with four equivalent O(1)U4 tetrahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_Er2U3O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.911
_cell_length_b   9.911
_cell_length_c   9.911
_cell_angle_alpha   158.033
_cell_angle_beta   148.326
_cell_angle_gamma   38.882
_symmetry_Int_Tables_number   1
_cell_volume   190.943
_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  0.703  0.703  0.000  1.0
  Er  Er1  1  0.297  0.297  0.000  1.0
  U  U2  1  0.901  0.901  0.000  1.0
  U  U3  1  0.500  0.500  0.000  1.0
  U  U4  1  0.099  0.099  0.000  1.0
  O  O5  1  0.280  0.000  0.280  1.0
  O  O6  1  0.839  0.602  0.237  1.0
  O  O7  1  0.432  0.194  0.239  1.0
  O  O8  1  0.045  0.806  0.239  1.0
  O  O9  1  0.636  0.398  0.237  1.0
  O  O10  1  0.720  0.000  0.720  1.0
  O  O11  1  0.364  0.602  0.763  1.0
  O  O12  1  0.955  0.194  0.761  1.0
  O  O13  1  0.568  0.806  0.761  1.0
  O  O14  1  0.161  0.398  0.763  1.0
  O  O15  1  0.000  0.500  0.500  1.0
[/CIF]
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