The compound described by LiFeSi2O6 crystallizes in the monoclinic Cc space group. Li(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with three equivalent Fe(1)O4 tetrahedra, and corners with three equivalent Si(2)O4 tetrahedra. Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form FeO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with three equivalent Li(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with three equivalent Li(1)O4 tetrahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Fe(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 Si(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. is represented by the CIF file [CIF]
data_LiFe(SiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.233
_cell_length_b   5.233
_cell_length_c   10.637
_cell_angle_alpha   76.151
_cell_angle_beta   76.151
_cell_angle_gamma   89.285
_symmetry_Int_Tables_number   1
_cell_volume   274.334
_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  0.844  0.650  0.332  1.0
  Li  Li1  1  0.650  0.844  0.832  1.0
  Fe  Fe2  1  0.752  0.032  0.506  1.0
  Fe  Fe3  1  0.032  0.752  0.006  1.0
  Si  Si4  1  0.002  0.340  0.832  1.0
  Si  Si5  1  0.591  0.449  0.663  1.0
  Si  Si6  1  0.449  0.591  0.163  1.0
  Si  Si7  1  0.340  0.002  0.332  1.0
  O  O8  1  0.957  0.629  0.864  1.0
  O  O9  1  0.613  0.760  0.664  1.0
  O  O10  1  0.390  0.691  0.015  1.0
  O  O11  1  0.760  0.613  0.164  1.0
  O  O12  1  0.971  0.109  0.967  1.0
  O  O13  1  0.773  0.271  0.758  1.0
  O  O14  1  0.691  0.390  0.515  1.0
  O  O15  1  0.290  0.329  0.730  1.0
  O  O16  1  0.329  0.290  0.230  1.0
  O  O17  1  0.109  0.971  0.467  1.0
  O  O18  1  0.629  0.957  0.364  1.0
  O  O19  1  0.271  0.773  0.258  1.0
[/CIF]
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The compound described by LiFeSi2O6 crystallizes in the monoclinic Cc space group. Li(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with three equivalent Fe(1)O4 tetrahedra, and corners with three equivalent Si(2)O4 tetrahedra. Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form FeO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with three equivalent Li(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(4), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form SiO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with three equivalent Li(1)O4 tetrahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Fe(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 Si(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. is represented by the CIF file [CIF]
data_LiFe(SiO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.233
_cell_length_b   5.233
_cell_length_c   10.637
_cell_angle_alpha   76.151
_cell_angle_beta   76.151
_cell_angle_gamma   89.285
_symmetry_Int_Tables_number   1
_cell_volume   274.334
_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  0.844  0.650  0.332  1.0
  Li  Li1  1  0.650  0.844  0.832  1.0
  Fe  Fe2  1  0.752  0.032  0.506  1.0
  Fe  Fe3  1  0.032  0.752  0.006  1.0
  Si  Si4  1  0.002  0.340  0.832  1.0
  Si  Si5  1  0.591  0.449  0.663  1.0
  Si  Si6  1  0.449  0.591  0.163  1.0
  Si  Si7  1  0.340  0.002  0.332  1.0
  O  O8  1  0.957  0.629  0.864  1.0
  O  O9  1  0.613  0.760  0.664  1.0
  O  O10  1  0.390  0.691  0.015  1.0
  O  O11  1  0.760  0.613  0.164  1.0
  O  O12  1  0.971  0.109  0.967  1.0
  O  O13  1  0.773  0.271  0.758  1.0
  O  O14  1  0.691  0.390  0.515  1.0
  O  O15  1  0.290  0.329  0.730  1.0
  O  O16  1  0.329  0.290  0.230  1.0
  O  O17  1  0.109  0.971  0.467  1.0
  O  O18  1  0.629  0.957  0.364  1.0
  O  O19  1  0.271  0.773  0.258  1.0
[/CIF]
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