The structure described by Li2FeSiO5 crystallizes in the orthorhombic Pmmn space group. Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted LiO6 octahedra that share corners with two equivalent Li(1)O6 octahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. Fe(1) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. Si(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with eight equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to four equivalent Li(1) and one Fe(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Li(1), one Fe(1), and one Si(1) atom. In the third O site, O(3) is bonded to two equivalent Li(1), one Fe(1), and one Si(1) atom to form distorted corner-sharing OLi2FeSi trigonal pyramids. is represented by the CIF file [CIF]
data_Li2FeSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.510
_cell_length_b   6.364
_cell_length_c   6.517
_cell_angle_alpha   89.998
_cell_angle_beta   90.013
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   187.073
_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
  Fe  Fe0  1  0.399  0.250  0.750  1.0
  Fe  Fe1  1  0.601  0.750  0.250  1.0
  Li  Li2  1  1.000  0.000  1.000  1.0
  Li  Li3  1  1.000  1.000  0.500  1.0
  Li  Li4  1  1.000  0.500  0.500  1.0
  Li  Li5  1  1.000  0.500  1.000  1.0
  O  O6  1  0.786  0.250  0.750  1.0
  O  O7  1  0.214  0.750  0.250  1.0
  O  O8  1  0.702  0.046  0.250  1.0
  O  O9  1  0.264  0.250  0.454  1.0
  O  O10  1  0.264  0.250  0.046  1.0
  O  O11  1  0.702  0.454  0.250  1.0
  O  O12  1  0.298  0.546  0.750  1.0
  O  O13  1  0.736  0.750  0.954  1.0
  O  O14  1  0.736  0.750  0.546  1.0
  O  O15  1  0.298  0.954  0.750  1.0
  Si  Si16  1  0.475  0.250  0.250  1.0
  Si  Si17  1  0.525  0.750  0.750  1.0
[/CIF]
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The structure described by Li2FeSiO5 crystallizes in the orthorhombic Pmmn space group. Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted LiO6 octahedra that share corners with two equivalent Li(1)O6 octahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with four equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. Fe(1) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. Si(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with eight equivalent Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to four equivalent Li(1) and one Fe(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Li(1), one Fe(1), and one Si(1) atom. In the third O site, O(3) is bonded to two equivalent Li(1), one Fe(1), and one Si(1) atom to form distorted corner-sharing OLi2FeSi trigonal pyramids. is represented by the CIF file [CIF]
data_Li2FeSiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.510
_cell_length_b   6.364
_cell_length_c   6.517
_cell_angle_alpha   89.998
_cell_angle_beta   90.013
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   187.073
_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
  Fe  Fe0  1  0.399  0.250  0.750  1.0
  Fe  Fe1  1  0.601  0.750  0.250  1.0
  Li  Li2  1  1.000  0.000  1.000  1.0
  Li  Li3  1  1.000  1.000  0.500  1.0
  Li  Li4  1  1.000  0.500  0.500  1.0
  Li  Li5  1  1.000  0.500  1.000  1.0
  O  O6  1  0.786  0.250  0.750  1.0
  O  O7  1  0.214  0.750  0.250  1.0
  O  O8  1  0.702  0.046  0.250  1.0
  O  O9  1  0.264  0.250  0.454  1.0
  O  O10  1  0.264  0.250  0.046  1.0
  O  O11  1  0.702  0.454  0.250  1.0
  O  O12  1  0.298  0.546  0.750  1.0
  O  O13  1  0.736  0.750  0.954  1.0
  O  O14  1  0.736  0.750  0.546  1.0
  O  O15  1  0.298  0.954  0.750  1.0
  Si  Si16  1  0.475  0.250  0.250  1.0
  Si  Si17  1  0.525  0.750  0.750  1.0
[/CIF]
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