The structure described by Li2FeSi3O8 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(4), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Li site, Li(2) is bonded in a trigonal non-coplanar geometry to one O(1), one O(6), and one O(7) atom. Fe(1) is bonded to one O(1), one O(4), one O(6), and one O(8) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(3), and one O(4) 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(1)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(5), one O(6), one O(7), and one O(8) 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(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Li(2), one Fe(1), and one Si(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Li(1), one Si(1), and one Si(2) 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(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Li(1), one Si(1), and one Si(3) atom. In the sixth O site, O(6) is bonded in a trigonal non-coplanar geometry to one Li(2), one Fe(1), and one Si(3) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(2), one Si(1), 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. is represented by the CIF file [CIF]
data_Li2FeSi3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.928
_cell_length_b   10.042
_cell_length_c   5.096
_cell_angle_alpha   90.000
_cell_angle_beta   91.008
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   354.462
_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  0.999  0.136  0.191  1.0
  Li  Li1  1  0.501  0.636  0.309  1.0
  Li  Li2  1  0.511  0.345  0.659  1.0
  Li  Li3  1  0.989  0.845  0.841  1.0
  Fe  Fe4  1  0.503  0.168  0.159  1.0
  Fe  Fe5  1  0.997  0.668  0.341  1.0
  Si  Si6  1  0.975  0.333  0.727  1.0
  Si  Si7  1  0.276  0.911  0.260  1.0
  Si  Si8  1  0.224  0.411  0.240  1.0
  Si  Si9  1  0.525  0.833  0.773  1.0
  Si  Si10  1  0.779  0.595  0.846  1.0
  Si  Si11  1  0.721  0.095  0.654  1.0
  O  O12  1  0.067  0.848  0.200  1.0
  O  O13  1  0.053  0.340  0.427  1.0
  O  O14  1  0.353  0.872  0.564  1.0
  O  O15  1  0.241  0.569  0.287  1.0
  O  O16  1  0.147  0.372  0.936  1.0
  O  O17  1  0.259  0.069  0.213  1.0
  O  O18  1  0.447  0.840  0.073  1.0
  O  O19  1  0.433  0.348  0.300  1.0
  O  O20  1  0.588  0.677  0.703  1.0
  O  O21  1  0.531  0.165  0.766  1.0
  O  O22  1  0.720  0.932  0.747  1.0
  O  O23  1  0.750  0.609  0.157  1.0
  O  O24  1  0.780  0.432  0.753  1.0
  O  O25  1  0.750  0.109  0.343  1.0
  O  O26  1  0.969  0.665  0.734  1.0
  O  O27  1  0.912  0.177  0.797  1.0
[/CIF]
.
The structure described by Li2FeSi3O8 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(4), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Li site, Li(2) is bonded in a trigonal non-coplanar geometry to one O(1), one O(6), and one O(7) atom. Fe(1) is bonded to one O(1), one O(4), one O(6), and one O(8) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(3), and one O(4) 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(1)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(5), one O(6), one O(7), and one O(8) 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(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Li(2), one Fe(1), and one Si(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Li(1), one Si(1), and one Si(2) 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(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Li(1), one Si(1), and one Si(3) atom. In the sixth O site, O(6) is bonded in a trigonal non-coplanar geometry to one Li(2), one Fe(1), and one Si(3) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(2), one Si(1), 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. is represented by the CIF file [CIF]
data_Li2FeSi3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.928
_cell_length_b   10.042
_cell_length_c   5.096
_cell_angle_alpha   90.000
_cell_angle_beta   91.008
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   354.462
_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  0.999  0.136  0.191  1.0
  Li  Li1  1  0.501  0.636  0.309  1.0
  Li  Li2  1  0.511  0.345  0.659  1.0
  Li  Li3  1  0.989  0.845  0.841  1.0
  Fe  Fe4  1  0.503  0.168  0.159  1.0
  Fe  Fe5  1  0.997  0.668  0.341  1.0
  Si  Si6  1  0.975  0.333  0.727  1.0
  Si  Si7  1  0.276  0.911  0.260  1.0
  Si  Si8  1  0.224  0.411  0.240  1.0
  Si  Si9  1  0.525  0.833  0.773  1.0
  Si  Si10  1  0.779  0.595  0.846  1.0
  Si  Si11  1  0.721  0.095  0.654  1.0
  O  O12  1  0.067  0.848  0.200  1.0
  O  O13  1  0.053  0.340  0.427  1.0
  O  O14  1  0.353  0.872  0.564  1.0
  O  O15  1  0.241  0.569  0.287  1.0
  O  O16  1  0.147  0.372  0.936  1.0
  O  O17  1  0.259  0.069  0.213  1.0
  O  O18  1  0.447  0.840  0.073  1.0
  O  O19  1  0.433  0.348  0.300  1.0
  O  O20  1  0.588  0.677  0.703  1.0
  O  O21  1  0.531  0.165  0.766  1.0
  O  O22  1  0.720  0.932  0.747  1.0
  O  O23  1  0.750  0.609  0.157  1.0
  O  O24  1  0.780  0.432  0.753  1.0
  O  O25  1  0.750  0.109  0.343  1.0
  O  O26  1  0.969  0.665  0.734  1.0
  O  O27  1  0.912  0.177  0.797  1.0
[/CIF]
.