The material described by Ba5Er2ZrAl2O13 crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted q6 geometry to three equivalent O(1) and six equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to three equivalent O(2) and nine equivalent O(1) atoms. In the third Ba site, Ba(3) is bonded in a 6-coordinate geometry to six equivalent O(2) atoms. Er(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form ErO6 octahedra that share corners with three equivalent Zr(1)O6 octahedra and corners with three equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 1°. Zr(1) is bonded to six equivalent O(1) atoms to form ZrO6 octahedra that share corners with six equivalent Er(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. Al(1) is bonded to one O(3) and three equivalent O(2) atoms to form AlO4 tetrahedra that share corners with three equivalent Er(1)O6 octahedra and  a cornercorner with one Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. There are three inequivalent O sites. In the first O site, O(3) is bonded in a linear geometry to two equivalent Al(1) atoms. In the second O site, O(1) is bonded to one Ba(1), three equivalent Ba(2), one Er(1), and one Zr(1) atom to form a mixture of distorted face, corner, and edge-sharing OBa4ErZr octahedra. The corner-sharing octahedral tilt angles range from 0-61°. In the third O site, O(2) is bonded in a 2-coordinate geometry to one Ba(2), one Ba(3), two equivalent Ba(1), one Er(1), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba5Er2ZrAl2O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.017
_cell_length_b   6.017
_cell_length_c   25.171
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   789.286
_cell_formula_units_Z   2
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
  Ba  Ba0  1  0.000  0.000  0.363  1.0
  Ba  Ba1  1  0.667  0.333  0.959  1.0
  Ba  Ba2  1  0.000  0.000  0.637  1.0
  Ba  Ba3  1  0.000  0.000  0.863  1.0
  Ba  Ba4  1  0.667  0.333  0.541  1.0
  Ba  Ba5  1  0.333  0.667  0.459  1.0
  Ba  Ba6  1  0.000  0.000  0.137  1.0
  Ba  Ba7  1  0.333  0.667  0.041  1.0
  Ba  Ba8  1  0.667  0.333  0.250  1.0
  Ba  Ba9  1  0.333  0.667  0.750  1.0
  Er  Er10  1  0.667  0.333  0.104  1.0
  Er  Er11  1  0.333  0.667  0.896  1.0
  Er  Er12  1  0.333  0.667  0.604  1.0
  Er  Er13  1  0.667  0.333  0.396  1.0
  Zr  Zr14  1  0.000  0.000  0.500  1.0
  Zr  Zr15  1  0.000  0.000  0.000  1.0
  Al  Al16  1  0.667  0.333  0.819  1.0
  Al  Al17  1  0.333  0.667  0.181  1.0
  Al  Al18  1  0.667  0.333  0.681  1.0
  Al  Al19  1  0.333  0.667  0.319  1.0
  O  O20  1  0.837  0.674  0.050  1.0
  O  O21  1  0.837  0.674  0.450  1.0
  O  O22  1  0.163  0.837  0.950  1.0
  O  O23  1  0.163  0.326  0.550  1.0
  O  O24  1  0.505  0.495  0.842  1.0
  O  O25  1  0.837  0.163  0.050  1.0
  O  O26  1  0.495  0.990  0.158  1.0
  O  O27  1  0.010  0.505  0.158  1.0
  O  O28  1  0.837  0.163  0.450  1.0
  O  O29  1  0.326  0.163  0.050  1.0
  O  O30  1  0.990  0.495  0.658  1.0
  O  O31  1  0.505  0.010  0.658  1.0
  O  O32  1  0.010  0.505  0.342  1.0
  O  O33  1  0.674  0.837  0.550  1.0
  O  O34  1  0.667  0.333  0.750  1.0
  O  O35  1  0.495  0.505  0.342  1.0
  O  O36  1  0.674  0.837  0.950  1.0
  O  O37  1  0.505  0.010  0.842  1.0
  O  O38  1  0.990  0.495  0.842  1.0
  O  O39  1  0.505  0.495  0.658  1.0
  O  O40  1  0.163  0.837  0.550  1.0
  O  O41  1  0.163  0.326  0.950  1.0
  O  O42  1  0.495  0.505  0.158  1.0
  O  O43  1  0.326  0.163  0.450  1.0
  O  O44  1  0.333  0.667  0.250  1.0
  O  O45  1  0.495  0.990  0.342  1.0
[/CIF]
.
The material described by Ba5Er2ZrAl2O13 crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted q6 geometry to three equivalent O(1) and six equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to three equivalent O(2) and nine equivalent O(1) atoms. In the third Ba site, Ba(3) is bonded in a 6-coordinate geometry to six equivalent O(2) atoms. Er(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form ErO6 octahedra that share corners with three equivalent Zr(1)O6 octahedra and corners with three equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 1°. Zr(1) is bonded to six equivalent O(1) atoms to form ZrO6 octahedra that share corners with six equivalent Er(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. Al(1) is bonded to one O(3) and three equivalent O(2) atoms to form AlO4 tetrahedra that share corners with three equivalent Er(1)O6 octahedra and  a cornercorner with one Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. There are three inequivalent O sites. In the first O site, O(3) is bonded in a linear geometry to two equivalent Al(1) atoms. In the second O site, O(1) is bonded to one Ba(1), three equivalent Ba(2), one Er(1), and one Zr(1) atom to form a mixture of distorted face, corner, and edge-sharing OBa4ErZr octahedra. The corner-sharing octahedral tilt angles range from 0-61°. In the third O site, O(2) is bonded in a 2-coordinate geometry to one Ba(2), one Ba(3), two equivalent Ba(1), one Er(1), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba5Er2ZrAl2O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.017
_cell_length_b   6.017
_cell_length_c   25.171
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   789.286
_cell_formula_units_Z   2
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
  Ba  Ba0  1  0.000  0.000  0.363  1.0
  Ba  Ba1  1  0.667  0.333  0.959  1.0
  Ba  Ba2  1  0.000  0.000  0.637  1.0
  Ba  Ba3  1  0.000  0.000  0.863  1.0
  Ba  Ba4  1  0.667  0.333  0.541  1.0
  Ba  Ba5  1  0.333  0.667  0.459  1.0
  Ba  Ba6  1  0.000  0.000  0.137  1.0
  Ba  Ba7  1  0.333  0.667  0.041  1.0
  Ba  Ba8  1  0.667  0.333  0.250  1.0
  Ba  Ba9  1  0.333  0.667  0.750  1.0
  Er  Er10  1  0.667  0.333  0.104  1.0
  Er  Er11  1  0.333  0.667  0.896  1.0
  Er  Er12  1  0.333  0.667  0.604  1.0
  Er  Er13  1  0.667  0.333  0.396  1.0
  Zr  Zr14  1  0.000  0.000  0.500  1.0
  Zr  Zr15  1  0.000  0.000  0.000  1.0
  Al  Al16  1  0.667  0.333  0.819  1.0
  Al  Al17  1  0.333  0.667  0.181  1.0
  Al  Al18  1  0.667  0.333  0.681  1.0
  Al  Al19  1  0.333  0.667  0.319  1.0
  O  O20  1  0.837  0.674  0.050  1.0
  O  O21  1  0.837  0.674  0.450  1.0
  O  O22  1  0.163  0.837  0.950  1.0
  O  O23  1  0.163  0.326  0.550  1.0
  O  O24  1  0.505  0.495  0.842  1.0
  O  O25  1  0.837  0.163  0.050  1.0
  O  O26  1  0.495  0.990  0.158  1.0
  O  O27  1  0.010  0.505  0.158  1.0
  O  O28  1  0.837  0.163  0.450  1.0
  O  O29  1  0.326  0.163  0.050  1.0
  O  O30  1  0.990  0.495  0.658  1.0
  O  O31  1  0.505  0.010  0.658  1.0
  O  O32  1  0.010  0.505  0.342  1.0
  O  O33  1  0.674  0.837  0.550  1.0
  O  O34  1  0.667  0.333  0.750  1.0
  O  O35  1  0.495  0.505  0.342  1.0
  O  O36  1  0.674  0.837  0.950  1.0
  O  O37  1  0.505  0.010  0.842  1.0
  O  O38  1  0.990  0.495  0.842  1.0
  O  O39  1  0.505  0.495  0.658  1.0
  O  O40  1  0.163  0.837  0.550  1.0
  O  O41  1  0.163  0.326  0.950  1.0
  O  O42  1  0.495  0.505  0.158  1.0
  O  O43  1  0.326  0.163  0.450  1.0
  O  O44  1  0.333  0.667  0.250  1.0
  O  O45  1  0.495  0.990  0.342  1.0
[/CIF]
.