The compound described by LiEr6Ta2O14 crystallizes in the monoclinic C2 space group. Li(1) is bonded in a 4-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms. There are four inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom. In the second Er site, Er(2) is bonded in a body-centered cubic geometry to two equivalent O(1), two equivalent O(3), two equivalent O(5), and two equivalent O(7) atoms. In the third Er site, Er(3) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(6), and two equivalent O(7) atoms. In the fourth Er site, Er(4) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted ErO7 pentagonal bipyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 40-45°. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Er(4)O7 pentagonal bipyramids, and edges with two equivalent Er(4)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 34°. In the second Ta site, Ta(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Er(4)O7 pentagonal bipyramids, and edges with two equivalent Er(4)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 34°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Er(1), one Er(2), one Er(3), and one Er(4) atom to form distorted OLiEr4 trigonal bipyramids that share corners with four equivalent O(7)Er4 tetrahedra,  a cornercorner with one O(1)LiEr4 trigonal bipyramid,  an edgeedge with one O(7)Er4 tetrahedra, edges with two equivalent O(5)Er3Ta tetrahedra, and  an edgeedge with one O(1)LiEr4 trigonal bipyramid. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Li(1), one Er(1), one Er(3), one Er(4), and one Ta(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(4), and one Ta(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Er(1), one Er(4), one Ta(1), and one Ta(2) atom. In the fifth O site, O(5) is bonded to one Er(1), one Er(2), one Er(4), and one Ta(1) atom to form distorted OEr3Ta tetrahedra that share corners with two equivalent O(5)Er3Ta tetrahedra, corners with four equivalent O(7)Er4 tetrahedra, and edges with two equivalent O(1)LiEr4 trigonal bipyramids. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Li(1), one Er(1), one Er(3), one Er(4), and one Ta(2) atom. In the seventh O site, O(7) is bonded to one Er(1), one Er(2), one Er(3), and one Er(4) atom to form OEr4 tetrahedra that share corners with two equivalent O(7)Er4 tetrahedra, corners with four equivalent O(5)Er3Ta tetrahedra, corners with four equivalent O(1)LiEr4 trigonal bipyramids, and  an edgeedge with one O(1)LiEr4 trigonal bipyramid. is represented by the CIF card [CIF]
data_LiEr6Ta2O14
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.407
_cell_length_b   6.407
_cell_length_c   7.563
_cell_angle_alpha   89.538
_cell_angle_beta   89.538
_cell_angle_gamma   109.688
_symmetry_Int_Tables_number   1
_cell_volume   292.259
_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
  Li  Li0  1  0.238  0.762  0.500  1.0
  Er  Er1  1  0.050  0.507  0.231  1.0
  Er  Er2  1  0.004  0.996  0.000  1.0
  Er  Er3  1  0.981  0.019  0.500  1.0
  Er  Er4  1  0.493  0.950  0.769  1.0
  Er  Er5  1  0.514  0.063  0.248  1.0
  Er  Er6  1  0.937  0.486  0.752  1.0
  Ta  Ta7  1  0.498  0.502  0.000  1.0
  Ta  Ta8  1  0.507  0.493  0.500  1.0
  O  O9  1  0.123  0.839  0.725  1.0
  O  O10  1  0.161  0.877  0.275  1.0
  O  O11  1  0.168  0.441  0.525  1.0
  O  O12  1  0.171  0.436  0.961  1.0
  O  O13  1  0.564  0.829  0.039  1.0
  O  O14  1  0.559  0.832  0.475  1.0
  O  O15  1  0.428  0.416  0.251  1.0
  O  O16  1  0.584  0.572  0.749  1.0
  O  O17  1  0.410  0.161  0.972  1.0
  O  O18  1  0.434  0.174  0.543  1.0
  O  O19  1  0.839  0.590  0.028  1.0
  O  O20  1  0.826  0.566  0.457  1.0
  O  O21  1  0.853  0.112  0.757  1.0
  O  O22  1  0.888  0.147  0.243  1.0
[/CIF]
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The compound described by LiEr6Ta2O14 crystallizes in the monoclinic C2 space group. Li(1) is bonded in a 4-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms. There are four inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom. In the second Er site, Er(2) is bonded in a body-centered cubic geometry to two equivalent O(1), two equivalent O(3), two equivalent O(5), and two equivalent O(7) atoms. In the third Er site, Er(3) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(6), and two equivalent O(7) atoms. In the fourth Er site, Er(4) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted ErO7 pentagonal bipyramids that share  a cornercorner with one Ta(1)O6 octahedra,  a cornercorner with one Ta(2)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 40-45°. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Er(4)O7 pentagonal bipyramids, and edges with two equivalent Er(4)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 34°. In the second Ta site, Ta(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Er(4)O7 pentagonal bipyramids, and edges with two equivalent Er(4)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 34°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Er(1), one Er(2), one Er(3), and one Er(4) atom to form distorted OLiEr4 trigonal bipyramids that share corners with four equivalent O(7)Er4 tetrahedra,  a cornercorner with one O(1)LiEr4 trigonal bipyramid,  an edgeedge with one O(7)Er4 tetrahedra, edges with two equivalent O(5)Er3Ta tetrahedra, and  an edgeedge with one O(1)LiEr4 trigonal bipyramid. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Li(1), one Er(1), one Er(3), one Er(4), and one Ta(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Er(1), one Er(2), one Er(4), and one Ta(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Er(1), one Er(4), one Ta(1), and one Ta(2) atom. In the fifth O site, O(5) is bonded to one Er(1), one Er(2), one Er(4), and one Ta(1) atom to form distorted OEr3Ta tetrahedra that share corners with two equivalent O(5)Er3Ta tetrahedra, corners with four equivalent O(7)Er4 tetrahedra, and edges with two equivalent O(1)LiEr4 trigonal bipyramids. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Li(1), one Er(1), one Er(3), one Er(4), and one Ta(2) atom. In the seventh O site, O(7) is bonded to one Er(1), one Er(2), one Er(3), and one Er(4) atom to form OEr4 tetrahedra that share corners with two equivalent O(7)Er4 tetrahedra, corners with four equivalent O(5)Er3Ta tetrahedra, corners with four equivalent O(1)LiEr4 trigonal bipyramids, and  an edgeedge with one O(1)LiEr4 trigonal bipyramid. is represented by the CIF card [CIF]
data_LiEr6Ta2O14
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.407
_cell_length_b   6.407
_cell_length_c   7.563
_cell_angle_alpha   89.538
_cell_angle_beta   89.538
_cell_angle_gamma   109.688
_symmetry_Int_Tables_number   1
_cell_volume   292.259
_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
  Li  Li0  1  0.238  0.762  0.500  1.0
  Er  Er1  1  0.050  0.507  0.231  1.0
  Er  Er2  1  0.004  0.996  0.000  1.0
  Er  Er3  1  0.981  0.019  0.500  1.0
  Er  Er4  1  0.493  0.950  0.769  1.0
  Er  Er5  1  0.514  0.063  0.248  1.0
  Er  Er6  1  0.937  0.486  0.752  1.0
  Ta  Ta7  1  0.498  0.502  0.000  1.0
  Ta  Ta8  1  0.507  0.493  0.500  1.0
  O  O9  1  0.123  0.839  0.725  1.0
  O  O10  1  0.161  0.877  0.275  1.0
  O  O11  1  0.168  0.441  0.525  1.0
  O  O12  1  0.171  0.436  0.961  1.0
  O  O13  1  0.564  0.829  0.039  1.0
  O  O14  1  0.559  0.832  0.475  1.0
  O  O15  1  0.428  0.416  0.251  1.0
  O  O16  1  0.584  0.572  0.749  1.0
  O  O17  1  0.410  0.161  0.972  1.0
  O  O18  1  0.434  0.174  0.543  1.0
  O  O19  1  0.839  0.590  0.028  1.0
  O  O20  1  0.826  0.566  0.457  1.0
  O  O21  1  0.853  0.112  0.757  1.0
  O  O22  1  0.888  0.147  0.243  1.0
[/CIF]
.