The compound described by LiTaOSiO4 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(5) atom. Ta(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra and corners with four equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. Si(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-44°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Li(1), one Ta(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1) and two equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Li(1), one Ta(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Ta(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Ta(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_LiTaSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.885
_cell_length_b   7.450
_cell_length_c   7.473
_cell_angle_alpha   60.536
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   382.155
_cell_formula_units_Z   4
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  0.433  0.248  0.309  1.0
  Li  Li1  1  0.567  0.752  0.691  1.0
  Li  Li2  1  0.067  0.248  0.809  1.0
  Li  Li3  1  0.933  0.752  0.191  1.0
  Ta  Ta4  1  0.740  0.252  0.007  1.0
  Ta  Ta5  1  0.760  0.252  0.507  1.0
  Ta  Ta6  1  0.260  0.748  0.993  1.0
  Ta  Ta7  1  0.240  0.748  0.493  1.0
  Si  Si8  1  0.611  0.750  0.259  1.0
  Si  Si9  1  0.889  0.750  0.759  1.0
  Si  Si10  1  0.111  0.250  0.241  1.0
  Si  Si11  1  0.389  0.250  0.741  1.0
  O  O12  1  0.757  0.558  0.853  1.0
  O  O13  1  0.328  0.751  0.748  1.0
  O  O14  1  0.261  0.055  0.852  1.0
  O  O15  1  0.672  0.249  0.252  1.0
  O  O16  1  0.512  0.264  0.909  1.0
  O  O17  1  0.993  0.242  0.066  1.0
  O  O18  1  0.488  0.736  0.091  1.0
  O  O19  1  0.239  0.055  0.352  1.0
  O  O20  1  0.743  0.558  0.353  1.0
  O  O21  1  0.988  0.264  0.409  1.0
  O  O22  1  0.761  0.945  0.648  1.0
  O  O23  1  0.493  0.758  0.434  1.0
  O  O24  1  0.828  0.249  0.752  1.0
  O  O25  1  0.507  0.242  0.566  1.0
  O  O26  1  0.172  0.751  0.248  1.0
  O  O27  1  0.012  0.736  0.591  1.0
  O  O28  1  0.739  0.945  0.148  1.0
  O  O29  1  0.007  0.758  0.934  1.0
  O  O30  1  0.243  0.442  0.147  1.0
  O  O31  1  0.257  0.442  0.647  1.0
[/CIF]
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The compound described by LiTaOSiO4 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(5) atom. Ta(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra and corners with four equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. Si(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-44°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Li(1), one Ta(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1) and two equivalent Ta(1) atoms. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Li(1), one Ta(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Ta(1) and one Si(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Ta(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_LiTaSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.885
_cell_length_b   7.450
_cell_length_c   7.473
_cell_angle_alpha   60.536
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   382.155
_cell_formula_units_Z   4
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  0.433  0.248  0.309  1.0
  Li  Li1  1  0.567  0.752  0.691  1.0
  Li  Li2  1  0.067  0.248  0.809  1.0
  Li  Li3  1  0.933  0.752  0.191  1.0
  Ta  Ta4  1  0.740  0.252  0.007  1.0
  Ta  Ta5  1  0.760  0.252  0.507  1.0
  Ta  Ta6  1  0.260  0.748  0.993  1.0
  Ta  Ta7  1  0.240  0.748  0.493  1.0
  Si  Si8  1  0.611  0.750  0.259  1.0
  Si  Si9  1  0.889  0.750  0.759  1.0
  Si  Si10  1  0.111  0.250  0.241  1.0
  Si  Si11  1  0.389  0.250  0.741  1.0
  O  O12  1  0.757  0.558  0.853  1.0
  O  O13  1  0.328  0.751  0.748  1.0
  O  O14  1  0.261  0.055  0.852  1.0
  O  O15  1  0.672  0.249  0.252  1.0
  O  O16  1  0.512  0.264  0.909  1.0
  O  O17  1  0.993  0.242  0.066  1.0
  O  O18  1  0.488  0.736  0.091  1.0
  O  O19  1  0.239  0.055  0.352  1.0
  O  O20  1  0.743  0.558  0.353  1.0
  O  O21  1  0.988  0.264  0.409  1.0
  O  O22  1  0.761  0.945  0.648  1.0
  O  O23  1  0.493  0.758  0.434  1.0
  O  O24  1  0.828  0.249  0.752  1.0
  O  O25  1  0.507  0.242  0.566  1.0
  O  O26  1  0.172  0.751  0.248  1.0
  O  O27  1  0.012  0.736  0.591  1.0
  O  O28  1  0.739  0.945  0.148  1.0
  O  O29  1  0.007  0.758  0.934  1.0
  O  O30  1  0.243  0.442  0.147  1.0
  O  O31  1  0.257  0.442  0.647  1.0
[/CIF]
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