The compound described by LiEr6Ta2O14 crystallizes in the monoclinic Pm space group. Li(1) is bonded in a 7-coordinate geometry to one O(10), one O(2), one O(5), two equivalent O(4), and two equivalent O(8) atoms. There are five inequivalent Er sites. In the first Er site, Er(1) is bonded to one O(10), one O(2), two equivalent O(3), and two equivalent O(8) atoms to form distorted ErO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra and corners with two equivalent Er(4)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 46-65°. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(7), and one O(9) atom. In the third Er site, Er(3) is bonded to one O(1), one O(6), one O(9), two equivalent O(4), and two equivalent O(7) atoms to form distorted ErO7 pentagonal bipyramids that share corners with two equivalent Ta(1)O6 octahedra, edges with two equivalent Ta(1)O6 octahedra, and edges with two equivalent Er(4)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 52°. In the fourth Er site, Er(4) is bonded to one O(10), one O(2), one O(5), two equivalent O(4), and two equivalent O(7) atoms to form ErO7 pentagonal bipyramids that share corners with two equivalent Er(1)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, edges with two equivalent Ta(1)O6 octahedra, and edges with two equivalent Er(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 31-68°. In the fifth Er site, Er(5) is bonded in a 7-coordinate geometry to one O(1), one O(6), one O(9), two equivalent O(3), and two equivalent O(8) atoms. Ta(1) is bonded to one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form TaO6 octahedra that share corners with two equivalent Er(1)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra,  a cornercorner with one Er(3)O7 pentagonal bipyramid,  a cornercorner with one Er(4)O7 pentagonal bipyramid,  an edgeedge with one Er(3)O7 pentagonal bipyramid, and  an edgeedge with one Er(4)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 25-65°. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Er(3), one Er(5), and two equivalent Er(2) atoms to form OEr4 tetrahedra that share corners with two equivalent O(9)Er4 tetrahedra, corners with four equivalent O(3)Er3Ta tetrahedra, corners with two equivalent O(10)LiEr4 trigonal bipyramids, corners with two equivalent O(2)LiEr4 trigonal bipyramids,  an edgeedge with one O(6)Er2Ta2 tetrahedra,  an edgeedge with one O(9)Er4 tetrahedra, and edges with two equivalent O(7)Er3Ta tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Er(1), one Er(4), and two equivalent Er(2) atoms to form distorted OLiEr4 trigonal bipyramids that share corners with two equivalent O(1)Er4 tetrahedra, corners with two equivalent O(9)Er4 tetrahedra, corners with four equivalent O(3)Er3Ta tetrahedra, corners with two equivalent O(10)LiEr4 trigonal bipyramids, edges with two equivalent O(7)Er3Ta tetrahedra, and  a faceface with one O(10)LiEr4 trigonal bipyramid. In the third O site, O(3) is bonded to one Er(1), one Er(2), one Er(5), and one Ta(1) atom to form OEr3Ta tetrahedra that share corners with two equivalent O(3)Er3Ta tetrahedra, corners with two equivalent O(1)Er4 tetrahedra, corners with two equivalent O(2)LiEr4 trigonal bipyramids,  an edgeedge with one O(6)Er2Ta2 tetrahedra,  an edgeedge with one O(7)Er3Ta tetrahedra,  an edgeedge with one O(9)Er4 tetrahedra, and  an edgeedge with one O(10)LiEr4 trigonal bipyramid. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Li(1), one Er(3), one Er(4), and one Ta(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Li(1), one Er(4), and two equivalent Ta(1) atoms. In the sixth O site, O(6) is bonded to one Er(3), one Er(5), and two equivalent Ta(1) atoms to form distorted OEr2Ta2 tetrahedra that share corners with two equivalent O(9)Er4 tetrahedra, corners with four equivalent O(7)Er3Ta tetrahedra,  an edgeedge with one O(1)Er4 tetrahedra, and edges with two equivalent O(3)Er3Ta tetrahedra. In the seventh O site, O(7) is bonded to one Er(2), one Er(3), one Er(4), and one Ta(1) atom to form OEr3Ta tetrahedra that share corners with two equivalent O(6)Er2Ta2 tetrahedra, corners with two equivalent O(7)Er3Ta tetrahedra, corners with two equivalent O(9)Er4 tetrahedra, corners with two equivalent O(10)LiEr4 trigonal bipyramids,  an edgeedge with one O(3)Er3Ta tetrahedra,  an edgeedge with one O(1)Er4 tetrahedra, and  an edgeedge with one O(2)LiEr4 trigonal bipyramid. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Li(1), one Er(1), one Er(5), and one Ta(1) atom. In the ninth O site, O(9) is bonded to one Er(3), one Er(5), and two equivalent Er(2) atoms to form OEr4 tetrahedra that share corners with two equivalent O(6)Er2Ta2 tetrahedra, corners with two equivalent O(1)Er4 tetrahedra, corners with four equivalent O(7)Er3Ta tetrahedra, corners with two equivalent O(10)LiEr4 trigonal bipyramids, corners with two equivalent O(2)LiEr4 trigonal bipyramids,  an edgeedge with one O(1)Er4 tetrahedra, and edges with two equivalent O(3)Er3Ta tetrahedra. In the tenth O site, O(10) is bonded to one Li(1), one Er(1), one Er(4), and two equivalent Er(2) atoms to form distorted OLiEr4 trigonal bipyramids that share corners with two equivalent O(1)Er4 tetrahedra, corners with two equivalent O(9)Er4 tetrahedra, corners with four equivalent O(7)Er3Ta tetrahedra, corners with two equivalent O(2)LiEr4 trigonal bipyramids, edges with two equivalent O(3)Er3Ta tetrahedra, and  a faceface with one O(2)LiEr4 trigonal bipyramid. is represented by the CIF card [CIF]
data_LiEr6Ta2O14
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.534
_cell_length_b   6.481
_cell_length_c   7.371
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.031
_symmetry_Int_Tables_number   1
_cell_volume   295.089
_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  0.743  0.746  0.250  1.0
  Er  Er1  1  0.039  0.485  0.250  1.0
  Er  Er2  1  0.043  0.021  0.991  1.0
  Er  Er3  1  0.043  0.021  0.509  1.0
  Er  Er4  1  0.500  0.947  0.750  1.0
  Er  Er5  1  0.504  0.036  0.250  1.0
  Er  Er6  1  0.997  0.482  0.750  1.0
  Ta  Ta7  1  0.506  0.479  0.983  1.0
  Ta  Ta8  1  0.506  0.479  0.517  1.0
  O  O9  1  0.126  0.841  0.750  1.0
  O  O10  1  0.137  0.862  0.250  1.0
  O  O11  1  0.165  0.387  0.503  1.0
  O  O12  1  0.165  0.387  0.997  1.0
  O  O13  1  0.554  0.790  0.049  1.0
  O  O14  1  0.554  0.790  0.451  1.0
  O  O15  1  0.481  0.407  0.250  1.0
  O  O16  1  0.425  0.586  0.750  1.0
  O  O17  1  0.420  0.148  0.968  1.0
  O  O18  1  0.420  0.148  0.532  1.0
  O  O19  1  0.821  0.547  0.016  1.0
  O  O20  1  0.821  0.547  0.484  1.0
  O  O21  1  0.859  0.106  0.750  1.0
  O  O22  1  0.869  0.120  0.250  1.0
[/CIF]
.
The compound described by LiEr6Ta2O14 crystallizes in the monoclinic Pm space group. Li(1) is bonded in a 7-coordinate geometry to one O(10), one O(2), one O(5), two equivalent O(4), and two equivalent O(8) atoms. There are five inequivalent Er sites. In the first Er site, Er(1) is bonded to one O(10), one O(2), two equivalent O(3), and two equivalent O(8) atoms to form distorted ErO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra and corners with two equivalent Er(4)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 46-65°. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(7), and one O(9) atom. In the third Er site, Er(3) is bonded to one O(1), one O(6), one O(9), two equivalent O(4), and two equivalent O(7) atoms to form distorted ErO7 pentagonal bipyramids that share corners with two equivalent Ta(1)O6 octahedra, edges with two equivalent Ta(1)O6 octahedra, and edges with two equivalent Er(4)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 52°. In the fourth Er site, Er(4) is bonded to one O(10), one O(2), one O(5), two equivalent O(4), and two equivalent O(7) atoms to form ErO7 pentagonal bipyramids that share corners with two equivalent Er(1)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra, edges with two equivalent Ta(1)O6 octahedra, and edges with two equivalent Er(3)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 31-68°. In the fifth Er site, Er(5) is bonded in a 7-coordinate geometry to one O(1), one O(6), one O(9), two equivalent O(3), and two equivalent O(8) atoms. Ta(1) is bonded to one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form TaO6 octahedra that share corners with two equivalent Er(1)O6 octahedra, corners with two equivalent Ta(1)O6 octahedra,  a cornercorner with one Er(3)O7 pentagonal bipyramid,  a cornercorner with one Er(4)O7 pentagonal bipyramid,  an edgeedge with one Er(3)O7 pentagonal bipyramid, and  an edgeedge with one Er(4)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 25-65°. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Er(3), one Er(5), and two equivalent Er(2) atoms to form OEr4 tetrahedra that share corners with two equivalent O(9)Er4 tetrahedra, corners with four equivalent O(3)Er3Ta tetrahedra, corners with two equivalent O(10)LiEr4 trigonal bipyramids, corners with two equivalent O(2)LiEr4 trigonal bipyramids,  an edgeedge with one O(6)Er2Ta2 tetrahedra,  an edgeedge with one O(9)Er4 tetrahedra, and edges with two equivalent O(7)Er3Ta tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Er(1), one Er(4), and two equivalent Er(2) atoms to form distorted OLiEr4 trigonal bipyramids that share corners with two equivalent O(1)Er4 tetrahedra, corners with two equivalent O(9)Er4 tetrahedra, corners with four equivalent O(3)Er3Ta tetrahedra, corners with two equivalent O(10)LiEr4 trigonal bipyramids, edges with two equivalent O(7)Er3Ta tetrahedra, and  a faceface with one O(10)LiEr4 trigonal bipyramid. In the third O site, O(3) is bonded to one Er(1), one Er(2), one Er(5), and one Ta(1) atom to form OEr3Ta tetrahedra that share corners with two equivalent O(3)Er3Ta tetrahedra, corners with two equivalent O(1)Er4 tetrahedra, corners with two equivalent O(2)LiEr4 trigonal bipyramids,  an edgeedge with one O(6)Er2Ta2 tetrahedra,  an edgeedge with one O(7)Er3Ta tetrahedra,  an edgeedge with one O(9)Er4 tetrahedra, and  an edgeedge with one O(10)LiEr4 trigonal bipyramid. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Li(1), one Er(3), one Er(4), and one Ta(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Li(1), one Er(4), and two equivalent Ta(1) atoms. In the sixth O site, O(6) is bonded to one Er(3), one Er(5), and two equivalent Ta(1) atoms to form distorted OEr2Ta2 tetrahedra that share corners with two equivalent O(9)Er4 tetrahedra, corners with four equivalent O(7)Er3Ta tetrahedra,  an edgeedge with one O(1)Er4 tetrahedra, and edges with two equivalent O(3)Er3Ta tetrahedra. In the seventh O site, O(7) is bonded to one Er(2), one Er(3), one Er(4), and one Ta(1) atom to form OEr3Ta tetrahedra that share corners with two equivalent O(6)Er2Ta2 tetrahedra, corners with two equivalent O(7)Er3Ta tetrahedra, corners with two equivalent O(9)Er4 tetrahedra, corners with two equivalent O(10)LiEr4 trigonal bipyramids,  an edgeedge with one O(3)Er3Ta tetrahedra,  an edgeedge with one O(1)Er4 tetrahedra, and  an edgeedge with one O(2)LiEr4 trigonal bipyramid. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Li(1), one Er(1), one Er(5), and one Ta(1) atom. In the ninth O site, O(9) is bonded to one Er(3), one Er(5), and two equivalent Er(2) atoms to form OEr4 tetrahedra that share corners with two equivalent O(6)Er2Ta2 tetrahedra, corners with two equivalent O(1)Er4 tetrahedra, corners with four equivalent O(7)Er3Ta tetrahedra, corners with two equivalent O(10)LiEr4 trigonal bipyramids, corners with two equivalent O(2)LiEr4 trigonal bipyramids,  an edgeedge with one O(1)Er4 tetrahedra, and edges with two equivalent O(3)Er3Ta tetrahedra. In the tenth O site, O(10) is bonded to one Li(1), one Er(1), one Er(4), and two equivalent Er(2) atoms to form distorted OLiEr4 trigonal bipyramids that share corners with two equivalent O(1)Er4 tetrahedra, corners with two equivalent O(9)Er4 tetrahedra, corners with four equivalent O(7)Er3Ta tetrahedra, corners with two equivalent O(2)LiEr4 trigonal bipyramids, edges with two equivalent O(3)Er3Ta tetrahedra, and  a faceface with one O(2)LiEr4 trigonal bipyramid. is represented by the CIF card [CIF]
data_LiEr6Ta2O14
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.534
_cell_length_b   6.481
_cell_length_c   7.371
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.031
_symmetry_Int_Tables_number   1
_cell_volume   295.089
_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  0.743  0.746  0.250  1.0
  Er  Er1  1  0.039  0.485  0.250  1.0
  Er  Er2  1  0.043  0.021  0.991  1.0
  Er  Er3  1  0.043  0.021  0.509  1.0
  Er  Er4  1  0.500  0.947  0.750  1.0
  Er  Er5  1  0.504  0.036  0.250  1.0
  Er  Er6  1  0.997  0.482  0.750  1.0
  Ta  Ta7  1  0.506  0.479  0.983  1.0
  Ta  Ta8  1  0.506  0.479  0.517  1.0
  O  O9  1  0.126  0.841  0.750  1.0
  O  O10  1  0.137  0.862  0.250  1.0
  O  O11  1  0.165  0.387  0.503  1.0
  O  O12  1  0.165  0.387  0.997  1.0
  O  O13  1  0.554  0.790  0.049  1.0
  O  O14  1  0.554  0.790  0.451  1.0
  O  O15  1  0.481  0.407  0.250  1.0
  O  O16  1  0.425  0.586  0.750  1.0
  O  O17  1  0.420  0.148  0.968  1.0
  O  O18  1  0.420  0.148  0.532  1.0
  O  O19  1  0.821  0.547  0.016  1.0
  O  O20  1  0.821  0.547  0.484  1.0
  O  O21  1  0.859  0.106  0.750  1.0
  O  O22  1  0.869  0.120  0.250  1.0
[/CIF]
.