The compound described by Li3Fe2(SiO4)2 is Clathrate-derived structured and crystallizes in the monoclinic P2_1 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, 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  an edgeedge with one Fe(2)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Fe(1)O4 tetrahedra. In the third Li site, Li(3) is bonded to one O(2), one O(4), one O(6), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Fe(1)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra, and  an edgeedge with one Li(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form FeO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one 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(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 Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. In the second Si site, Si(2) 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 Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Fe(2), and one Si(1) atom to form distorted corner-sharing OLi2FeSi tetrahedra. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(3), one Fe(2), and one Si(1) 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(1) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Li(2), one Li(3), one Fe(1), and one Si(1) atom. In the fifth O site, O(5) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(2) atom to form distorted corner-sharing OLi2FeSi tetrahedra. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Li(3), one Fe(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(2), and one Si(2) atom. In the eighth O site, O(8) is bonded to one Li(2), one Li(3), one Fe(2), and one Si(2) atom to form corner-sharing OLi2FeSi tetrahedra. is represented by the CIF file [CIF]
data_Li3Fe2(SiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.316
_cell_length_b   5.174
_cell_length_c   6.105
_cell_angle_alpha   88.828
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   357.383
_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  0.834  0.552  0.758  1.0
  Li  Li1  1  0.334  0.448  0.242  1.0
  Li  Li2  1  0.172  0.962  0.241  1.0
  Li  Li3  1  0.670  0.052  0.243  1.0
  Li  Li4  1  0.672  0.038  0.759  1.0
  Li  Li5  1  0.170  0.948  0.757  1.0
  Fe  Fe6  1  0.573  0.439  0.500  1.0
  Fe  Fe7  1  0.073  0.561  0.500  1.0
  Fe  Fe8  1  0.424  0.068  0.974  1.0
  Fe  Fe9  1  0.924  0.932  0.026  1.0
  Si  Si10  1  0.409  0.937  0.492  1.0
  Si  Si11  1  0.909  0.063  0.508  1.0
  Si  Si12  1  0.585  0.565  0.005  1.0
  Si  Si13  1  0.085  0.435  0.995  1.0
  O  O14  1  0.838  0.952  0.725  1.0
  O  O15  1  0.334  0.993  0.710  1.0
  O  O16  1  0.934  0.377  0.534  1.0
  O  O17  1  0.545  0.070  0.509  1.0
  O  O18  1  0.434  0.623  0.466  1.0
  O  O19  1  0.045  0.930  0.491  1.0
  O  O20  1  0.834  0.007  0.290  1.0
  O  O21  1  0.338  0.048  0.275  1.0
  O  O22  1  0.157  0.536  0.222  1.0
  O  O23  1  0.653  0.451  0.228  1.0
  O  O24  1  0.451  0.454  0.004  1.0
  O  O25  1  0.951  0.546  0.996  1.0
  O  O26  1  0.589  0.883  0.004  1.0
  O  O27  1  0.089  0.117  0.996  1.0
  O  O28  1  0.657  0.464  0.778  1.0
  O  O29  1  0.153  0.549  0.772  1.0
[/CIF]
.
The compound described by Li3Fe2(SiO4)2 is Clathrate-derived structured and crystallizes in the monoclinic P2_1 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, 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  an edgeedge with one Fe(2)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Fe(1)O4 tetrahedra. In the third Li site, Li(3) is bonded to one O(2), one O(4), one O(6), and one O(8) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Fe(1)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra, and  an edgeedge with one Li(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(7), and one O(8) atom to form FeO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one 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(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 Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. In the second Si site, Si(2) 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 Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Fe(2), and one Si(1) atom to form distorted corner-sharing OLi2FeSi tetrahedra. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(3), one Fe(2), and one Si(1) 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(1) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Li(2), one Li(3), one Fe(1), and one Si(1) atom. In the fifth O site, O(5) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(2) atom to form distorted corner-sharing OLi2FeSi tetrahedra. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Li(3), one Fe(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(2), and one Si(2) atom. In the eighth O site, O(8) is bonded to one Li(2), one Li(3), one Fe(2), and one Si(2) atom to form corner-sharing OLi2FeSi tetrahedra. is represented by the CIF file [CIF]
data_Li3Fe2(SiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.316
_cell_length_b   5.174
_cell_length_c   6.105
_cell_angle_alpha   88.828
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   357.383
_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  0.834  0.552  0.758  1.0
  Li  Li1  1  0.334  0.448  0.242  1.0
  Li  Li2  1  0.172  0.962  0.241  1.0
  Li  Li3  1  0.670  0.052  0.243  1.0
  Li  Li4  1  0.672  0.038  0.759  1.0
  Li  Li5  1  0.170  0.948  0.757  1.0
  Fe  Fe6  1  0.573  0.439  0.500  1.0
  Fe  Fe7  1  0.073  0.561  0.500  1.0
  Fe  Fe8  1  0.424  0.068  0.974  1.0
  Fe  Fe9  1  0.924  0.932  0.026  1.0
  Si  Si10  1  0.409  0.937  0.492  1.0
  Si  Si11  1  0.909  0.063  0.508  1.0
  Si  Si12  1  0.585  0.565  0.005  1.0
  Si  Si13  1  0.085  0.435  0.995  1.0
  O  O14  1  0.838  0.952  0.725  1.0
  O  O15  1  0.334  0.993  0.710  1.0
  O  O16  1  0.934  0.377  0.534  1.0
  O  O17  1  0.545  0.070  0.509  1.0
  O  O18  1  0.434  0.623  0.466  1.0
  O  O19  1  0.045  0.930  0.491  1.0
  O  O20  1  0.834  0.007  0.290  1.0
  O  O21  1  0.338  0.048  0.275  1.0
  O  O22  1  0.157  0.536  0.222  1.0
  O  O23  1  0.653  0.451  0.228  1.0
  O  O24  1  0.451  0.454  0.004  1.0
  O  O25  1  0.951  0.546  0.996  1.0
  O  O26  1  0.589  0.883  0.004  1.0
  O  O27  1  0.089  0.117  0.996  1.0
  O  O28  1  0.657  0.464  0.778  1.0
  O  O29  1  0.153  0.549  0.772  1.0
[/CIF]
.