The compound described by Lu3TaO7 crystallizes in the orthorhombic C222_1 space group. There are two inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to one O(1), one O(2), one O(4), two equivalent O(3), and two equivalent O(5) atoms to form distorted LuO7 pentagonal bipyramids that share corners with two equivalent Ta(1)O6 octahedra,  a cornercorner with one Lu(1)O7 pentagonal bipyramid, edges with two equivalent Ta(1)O6 octahedra, and edges with three equivalent Lu(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-49°. In the second Lu site, Lu(2) is bonded in a distorted body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. Ta(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with four equivalent Lu(1)O7 pentagonal bipyramids, and edges with four equivalent Lu(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 45°. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Lu(1) and two equivalent Ta(1) atoms to form distorted OLu2Ta2 tetrahedra that share corners with two equivalent O(1)Lu2Ta2 tetrahedra, corners with two equivalent O(4)Lu4 tetrahedra, corners with four equivalent O(5)Lu3Ta tetrahedra,  an edgeedge with one O(2)Lu4 tetrahedra, and edges with two equivalent O(5)Lu3Ta tetrahedra. In the second O site, O(2) is bonded to two equivalent Lu(1) and two equivalent Lu(2) atoms to form OLu4 tetrahedra that share corners with two equivalent O(2)Lu4 tetrahedra, corners with four equivalent O(5)Lu3Ta tetrahedra, corners with four equivalent O(4)Lu4 tetrahedra,  an edgeedge with one O(1)Lu2Ta2 tetrahedra,  an edgeedge with one O(4)Lu4 tetrahedra, and edges with two equivalent O(5)Lu3Ta tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Lu(2), two equivalent Lu(1), and one Ta(1) atom. In the fourth O site, O(4) is bonded to two equivalent Lu(1) and two equivalent Lu(2) atoms to form OLu4 tetrahedra that share corners with two equivalent O(1)Lu2Ta2 tetrahedra, corners with two equivalent O(4)Lu4 tetrahedra, corners with four equivalent O(5)Lu3Ta tetrahedra, corners with four equivalent O(2)Lu4 tetrahedra,  an edgeedge with one O(2)Lu4 tetrahedra, and edges with two equivalent O(5)Lu3Ta tetrahedra. In the fifth O site, O(5) is bonded to one Lu(2), two equivalent Lu(1), and one Ta(1) atom to form distorted OLu3Ta tetrahedra that share corners with two equivalent O(1)Lu2Ta2 tetrahedra, corners with two equivalent O(5)Lu3Ta tetrahedra, corners with two equivalent O(2)Lu4 tetrahedra, corners with two equivalent O(4)Lu4 tetrahedra,  an edgeedge with one O(1)Lu2Ta2 tetrahedra,  an edgeedge with one O(5)Lu3Ta tetrahedra,  an edgeedge with one O(2)Lu4 tetrahedra, and  an edgeedge with one O(4)Lu4 tetrahedra. is represented by the CIF file [CIF]
data_Lu3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.351
_cell_length_b   6.351
_cell_length_c   7.355
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.007
_symmetry_Int_Tables_number   1
_cell_volume   280.530
_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
  Lu  Lu0  1  0.466  0.998  0.253  1.0
  Lu  Lu1  1  0.002  0.534  0.247  1.0
  Lu  Lu2  1  0.474  0.474  0.000  1.0
  Lu  Lu3  1  0.526  0.526  0.500  1.0
  Lu  Lu4  1  0.534  0.002  0.753  1.0
  Lu  Lu5  1  0.998  0.466  0.747  1.0
  Ta  Ta6  1  0.003  0.003  0.500  1.0
  Ta  Ta7  1  0.997  0.997  0.000  1.0
  O  O8  1  0.926  0.074  0.750  1.0
  O  O9  1  0.640  0.360  0.750  1.0
  O  O10  1  0.319  0.061  0.540  1.0
  O  O11  1  0.939  0.681  0.960  1.0
  O  O12  1  0.629  0.371  0.250  1.0
  O  O13  1  0.918  0.670  0.531  1.0
  O  O14  1  0.330  0.082  0.969  1.0
  O  O15  1  0.082  0.330  0.031  1.0
  O  O16  1  0.670  0.918  0.469  1.0
  O  O17  1  0.371  0.629  0.750  1.0
  O  O18  1  0.681  0.939  0.040  1.0
  O  O19  1  0.061  0.319  0.460  1.0
  O  O20  1  0.360  0.640  0.250  1.0
  O  O21  1  0.074  0.926  0.250  1.0
[/CIF]
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The compound described by Lu3TaO7 crystallizes in the orthorhombic C222_1 space group. There are two inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to one O(1), one O(2), one O(4), two equivalent O(3), and two equivalent O(5) atoms to form distorted LuO7 pentagonal bipyramids that share corners with two equivalent Ta(1)O6 octahedra,  a cornercorner with one Lu(1)O7 pentagonal bipyramid, edges with two equivalent Ta(1)O6 octahedra, and edges with three equivalent Lu(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-49°. In the second Lu site, Lu(2) is bonded in a distorted body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. Ta(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with four equivalent Lu(1)O7 pentagonal bipyramids, and edges with four equivalent Lu(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 45°. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Lu(1) and two equivalent Ta(1) atoms to form distorted OLu2Ta2 tetrahedra that share corners with two equivalent O(1)Lu2Ta2 tetrahedra, corners with two equivalent O(4)Lu4 tetrahedra, corners with four equivalent O(5)Lu3Ta tetrahedra,  an edgeedge with one O(2)Lu4 tetrahedra, and edges with two equivalent O(5)Lu3Ta tetrahedra. In the second O site, O(2) is bonded to two equivalent Lu(1) and two equivalent Lu(2) atoms to form OLu4 tetrahedra that share corners with two equivalent O(2)Lu4 tetrahedra, corners with four equivalent O(5)Lu3Ta tetrahedra, corners with four equivalent O(4)Lu4 tetrahedra,  an edgeedge with one O(1)Lu2Ta2 tetrahedra,  an edgeedge with one O(4)Lu4 tetrahedra, and edges with two equivalent O(5)Lu3Ta tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Lu(2), two equivalent Lu(1), and one Ta(1) atom. In the fourth O site, O(4) is bonded to two equivalent Lu(1) and two equivalent Lu(2) atoms to form OLu4 tetrahedra that share corners with two equivalent O(1)Lu2Ta2 tetrahedra, corners with two equivalent O(4)Lu4 tetrahedra, corners with four equivalent O(5)Lu3Ta tetrahedra, corners with four equivalent O(2)Lu4 tetrahedra,  an edgeedge with one O(2)Lu4 tetrahedra, and edges with two equivalent O(5)Lu3Ta tetrahedra. In the fifth O site, O(5) is bonded to one Lu(2), two equivalent Lu(1), and one Ta(1) atom to form distorted OLu3Ta tetrahedra that share corners with two equivalent O(1)Lu2Ta2 tetrahedra, corners with two equivalent O(5)Lu3Ta tetrahedra, corners with two equivalent O(2)Lu4 tetrahedra, corners with two equivalent O(4)Lu4 tetrahedra,  an edgeedge with one O(1)Lu2Ta2 tetrahedra,  an edgeedge with one O(5)Lu3Ta tetrahedra,  an edgeedge with one O(2)Lu4 tetrahedra, and  an edgeedge with one O(4)Lu4 tetrahedra. is represented by the CIF file [CIF]
data_Lu3TaO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.351
_cell_length_b   6.351
_cell_length_c   7.355
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.007
_symmetry_Int_Tables_number   1
_cell_volume   280.530
_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
  Lu  Lu0  1  0.466  0.998  0.253  1.0
  Lu  Lu1  1  0.002  0.534  0.247  1.0
  Lu  Lu2  1  0.474  0.474  0.000  1.0
  Lu  Lu3  1  0.526  0.526  0.500  1.0
  Lu  Lu4  1  0.534  0.002  0.753  1.0
  Lu  Lu5  1  0.998  0.466  0.747  1.0
  Ta  Ta6  1  0.003  0.003  0.500  1.0
  Ta  Ta7  1  0.997  0.997  0.000  1.0
  O  O8  1  0.926  0.074  0.750  1.0
  O  O9  1  0.640  0.360  0.750  1.0
  O  O10  1  0.319  0.061  0.540  1.0
  O  O11  1  0.939  0.681  0.960  1.0
  O  O12  1  0.629  0.371  0.250  1.0
  O  O13  1  0.918  0.670  0.531  1.0
  O  O14  1  0.330  0.082  0.969  1.0
  O  O15  1  0.082  0.330  0.031  1.0
  O  O16  1  0.670  0.918  0.469  1.0
  O  O17  1  0.371  0.629  0.750  1.0
  O  O18  1  0.681  0.939  0.040  1.0
  O  O19  1  0.061  0.319  0.460  1.0
  O  O20  1  0.360  0.640  0.250  1.0
  O  O21  1  0.074  0.926  0.250  1.0
[/CIF]
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