The compound described by LiFeSi2O6 crystallizes in the triclinic P1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a trigonal non-coplanar geometry to one O(4), one O(6), and one O(8) atom. In the second Li site, Li(2) is bonded in a trigonal non-coplanar geometry to one O(10), one O(5), and one O(7) atom. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(5), one O(6), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(10), one O(4), one O(7), and one O(9) atom to form FeO4 tetrahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(12), one O(2), and one O(3) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(10), one O(3), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(11), one O(5), one O(7), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Fe(1)O4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(1), one O(11), one O(12), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one Si(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(1), one Fe(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Li(2), one Fe(1), and one Si(3) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(2), one Fe(2), and one Si(3) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(3) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Fe(2) and one Si(4) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Li(2), one Fe(2), and one Si(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(4) atom. is represented by the CIF card [CIF]
data_LiFe(SiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.115
_cell_length_b   7.858
_cell_length_c   8.889
_cell_angle_alpha   65.283
_cell_angle_beta   89.535
_cell_angle_gamma   89.240
_symmetry_Int_Tables_number   1
_cell_volume   324.509
_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
  Li  Li0  1  0.637  0.870  0.301  1.0
  Li  Li1  1  0.136  0.091  0.714  1.0
  Fe  Fe2  1  0.127  0.064  0.378  1.0
  Fe  Fe3  1  0.647  0.091  0.897  1.0
  Si  Si4  1  0.184  0.497  0.096  1.0
  Si  Si5  1  0.147  0.895  0.106  1.0
  Si  Si6  1  0.628  0.928  0.620  1.0
  Si  Si7  1  0.687  0.511  0.886  1.0
  O  O8  1  0.475  0.456  0.039  1.0
  O  O9  1  0.086  0.318  0.258  1.0
  O  O10  1  0.208  0.677  0.144  1.0
  O  O11  1  0.830  0.938  0.097  1.0
  O  O12  1  0.337  0.025  0.566  1.0
  O  O13  1  0.274  0.931  0.259  1.0
  O  O14  1  0.777  0.028  0.725  1.0
  O  O15  1  0.794  0.953  0.454  1.0
  O  O16  1  0.707  0.343  0.824  1.0
  O  O17  1  0.284  0.034  0.928  1.0
  O  O18  1  0.588  0.704  0.733  1.0
  O  O19  1  0.976  0.549  0.943  1.0
[/CIF]
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The compound described by LiFeSi2O6 crystallizes in the triclinic P1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a trigonal non-coplanar geometry to one O(4), one O(6), and one O(8) atom. In the second Li site, Li(2) is bonded in a trigonal non-coplanar geometry to one O(10), one O(5), and one O(7) atom. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(5), one O(6), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(10), one O(4), one O(7), and one O(9) atom to form FeO4 tetrahedra that share  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(12), one O(2), and one O(3) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(10), one O(3), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(11), one O(5), one O(7), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(2)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, and corners with two equivalent Fe(1)O4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(1), one O(11), one O(12), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one Si(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(1), one Fe(2), and one Si(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Li(2), one Fe(1), and one Si(3) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(2), one Fe(2), and one Si(3) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(3) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Fe(2) and one Si(4) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Li(2), one Fe(2), and one Si(2) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(4) atom. is represented by the CIF card [CIF]
data_LiFe(SiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.115
_cell_length_b   7.858
_cell_length_c   8.889
_cell_angle_alpha   65.283
_cell_angle_beta   89.535
_cell_angle_gamma   89.240
_symmetry_Int_Tables_number   1
_cell_volume   324.509
_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
  Li  Li0  1  0.637  0.870  0.301  1.0
  Li  Li1  1  0.136  0.091  0.714  1.0
  Fe  Fe2  1  0.127  0.064  0.378  1.0
  Fe  Fe3  1  0.647  0.091  0.897  1.0
  Si  Si4  1  0.184  0.497  0.096  1.0
  Si  Si5  1  0.147  0.895  0.106  1.0
  Si  Si6  1  0.628  0.928  0.620  1.0
  Si  Si7  1  0.687  0.511  0.886  1.0
  O  O8  1  0.475  0.456  0.039  1.0
  O  O9  1  0.086  0.318  0.258  1.0
  O  O10  1  0.208  0.677  0.144  1.0
  O  O11  1  0.830  0.938  0.097  1.0
  O  O12  1  0.337  0.025  0.566  1.0
  O  O13  1  0.274  0.931  0.259  1.0
  O  O14  1  0.777  0.028  0.725  1.0
  O  O15  1  0.794  0.953  0.454  1.0
  O  O16  1  0.707  0.343  0.824  1.0
  O  O17  1  0.284  0.034  0.928  1.0
  O  O18  1  0.588  0.704  0.733  1.0
  O  O19  1  0.976  0.549  0.943  1.0
[/CIF]
.