The compound described by Li9Fe4(SiO5)4 crystallizes in the triclinic P1 space group. There are nine inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(13), one O(2), one O(6), and one O(9) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(2)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Li(7)O4 tetrahedra, corners with two equivalent Li(9)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(1), one O(10), one O(14), and one O(5) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the third Li site, Li(3) is bonded to one O(12), one O(3), one O(7), and one O(8) atom to form LiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra, corners with two equivalent Fe(3)O4 tetrahedra, corners with two equivalent Fe(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. In the fourth Li site, Li(4) is bonded to one O(10), one O(16), one O(4), and one O(5) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(2)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the fifth Li site, Li(5) is bonded to one O(12), one O(15), one O(20), and one O(3) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(3)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(9)O4 tetrahedra, corners with two equivalent Fe(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. In the sixth Li site, Li(6) is bonded to one O(11), one O(16), one O(19), and one O(4) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(4)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, corners with two equivalent Fe(3)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. In the seventh Li site, Li(7) is bonded to one O(13), one O(17), one O(18), and one O(2) atom to form LiO4 tetrahedra that share  a cornercorner with one Li(9)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the eighth Li site, Li(8) is bonded to one O(14), one O(16), one O(19), and one O(5) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(3)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the ninth Li site, Li(9) is bonded to one O(13), one O(15), one O(20), and one O(6) atom to form LiO4 tetrahedra that share  a cornercorner with one Li(7)O4 tetrahedra,  a cornercorner with one Fe(4)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(17), one O(2), and one O(9) atom to form FeO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(7)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(10), one O(18), and one O(2) atom to form FeO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra,  a cornercorner with one Li(4)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(7)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the third Fe site, Fe(3) is bonded to one O(11), one O(12), one O(19), and one O(7) atom to form FeO4 tetrahedra that share  a cornercorner with one Li(5)O4 tetrahedra,  a cornercorner with one Li(8)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, corners with two equivalent Fe(4)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. In the fourth Fe site, Fe(4) is bonded to one O(11), one O(12), one O(20), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Li(6)O4 tetrahedra,  a cornercorner with one Li(9)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra, corners with two equivalent Fe(3)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(19), one O(4), one O(5), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, and corners with two equivalent Fe(3)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(20), one O(3), one O(6), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra, corners with two equivalent Li(9)O4 tetrahedra, and corners with two equivalent Fe(4)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(13), one O(15), one O(17), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Li(5)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(7)O4 tetrahedra, corners with two equivalent Li(9)O4 tetrahedra, and corners with two equivalent Fe(1)O4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(10), one O(14), one O(16), and one O(18) atom to form SiO4 tetrahedra that share  a cornercorner with one Li(6)O4 tetrahedra,  a cornercorner with one Li(7)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. There are twenty inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(2), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded to one Li(1), one Li(7), one Fe(1), and one Fe(2) atom to form OLi2Fe2 tetrahedra that share  a cornercorner with one O(10)Li2FeSi tetrahedra and corners with two equivalent O(13)Li3Si tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(3), one Li(5), and one Si(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(4), one Li(6), and one Si(1) atom. In the fifth O site, O(5) is bonded to one Li(2), one Li(4), one Li(8), and one Si(1) atom to form OLi3Si tetrahedra that share corners with two equivalent O(10)Li2FeSi tetrahedra, corners with two equivalent O(19)Li2FeSi tetrahedra, and corners with two equivalent O(16)Li3Si tetrahedra. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Li(1), one Li(9), and one Si(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(3), one Fe(3), and one Si(1) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Li(3), one Fe(4), and one Si(2) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(3) atom. In the tenth O site, O(10) is bonded to one Li(2), one Li(4), one Fe(2), and one Si(4) atom to form OLi2FeSi tetrahedra that share  a cornercorner with one O(2)Li2Fe2 tetrahedra, corners with two equivalent O(16)Li3Si tetrahedra, and corners with two equivalent O(5)Li3Si tetrahedra. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Li(6), one Fe(3), and one Fe(4) atom. In the twelfth O site, O(12) is bonded to one Li(3), one Li(5), one Fe(3), and one Fe(4) atom to form corner-sharing OLi2Fe2 tetrahedra. In the thirteenth O site, O(13) is bonded to one Li(1), one Li(7), one Li(9), and one Si(3) atom to form distorted OLi3Si tetrahedra that share  a cornercorner with one O(20)Li2FeSi tetrahedra and corners with two equivalent O(2)Li2Fe2 tetrahedra. In the fourteenth O site, O(14) is bonded in a trigonal planar geometry to one Li(2), one Li(8), and one Si(4) atom. In the fifteenth O site, O(15) is bonded in a trigonal planar geometry to one Li(5), one Li(9), and one Si(3) atom. In the sixteenth O site, O(16) is bonded to one Li(4), one Li(6), one Li(8), and one Si(4) atom to form OLi3Si tetrahedra that share corners with two equivalent O(10)Li2FeSi tetrahedra, corners with two equivalent O(19)Li2FeSi tetrahedra, and corners with two equivalent O(5)Li3Si tetrahedra. In the seventeenth O site, O(17) is bonded in a trigonal planar geometry to one Li(7), one Fe(1), and one Si(3) atom. In the eighteenth O site, O(18) is bonded in a trigonal planar geometry to one Li(7), one Fe(2), and one Si(4) atom. In the nineteenth O site, O(19) is bonded to one Li(6), one Li(8), one Fe(3), and one Si(1) atom to form OLi2FeSi tetrahedra that share  a cornercorner with one O(12)Li2Fe2 tetrahedra, corners with two equivalent O(16)Li3Si tetrahedra, and corners with two equivalent O(5)Li3Si tetrahedra. In the twentieth O site, O(20) is bonded to one Li(5), one Li(9), one Fe(4), and one Si(2) atom to form OLi2FeSi tetrahedra that share  a cornercorner with one O(13)Li3Si tetrahedra and corners with two equivalent O(12)Li2Fe2 tetrahedra. is represented by the CIF file [CIF]
data_Li9Fe4(SiO5)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.013
_cell_length_b   5.618
_cell_length_c   16.184
_cell_angle_alpha   90.288
_cell_angle_beta   89.978
_cell_angle_gamma   89.639
_symmetry_Int_Tables_number   1
_cell_volume   455.754
_cell_formula_units_Z   1
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  0.994  0.662  0.599  1.0
  Li  Li1  1  0.998  0.166  0.909  1.0
  Li  Li2  1  0.001  0.171  0.301  1.0
  Li  Li3  1  0.997  0.659  0.002  1.0
  Li  Li4  1  0.498  0.337  0.403  1.0
  Li  Li5  1  0.502  0.831  0.092  1.0
  Li  Li6  1  0.510  0.825  0.696  1.0
  Li  Li7  1  0.497  0.339  0.997  1.0
  Li  Li8  1  0.502  0.836  0.506  1.0
  Fe  Fe9  1  0.001  0.169  0.702  1.0
  Fe  Fe10  1  0.007  0.667  0.802  1.0
  Fe  Fe11  1  0.503  0.333  0.199  1.0
  Fe  Fe12  1  0.504  0.836  0.301  1.0
  Si  Si13  1  0.005  0.168  0.096  1.0
  Si  Si14  1  0.009  0.671  0.400  1.0
  Si  Si15  1  0.500  0.338  0.599  1.0
  Si  Si16  1  0.508  0.830  0.903  1.0
  O  O17  1  0.058  0.336  0.801  1.0
  O  O18  1  0.107  0.842  0.706  1.0
  O  O19  1  0.121  0.405  0.381  1.0
  O  O20  1  0.110  0.895  0.081  1.0
  O  O21  1  0.103  0.323  0.017  1.0
  O  O22  1  0.116  0.753  0.491  1.0
  O  O23  1  0.133  0.261  0.185  1.0
  O  O24  1  0.133  0.852  0.330  1.0
  O  O25  1  0.174  0.344  0.619  1.0
  O  O26  1  0.176  0.816  0.895  1.0
  O  O27  1  0.556  0.663  0.202  1.0
  O  O28  1  0.608  0.161  0.295  1.0
  O  O29  1  0.609  0.610  0.601  1.0
  O  O30  1  0.609  0.104  0.918  1.0
  O  O31  1  0.531  0.193  0.510  1.0
  O  O32  1  0.606  0.674  0.983  1.0
  O  O33  1  0.637  0.162  0.670  1.0
  O  O34  1  0.635  0.736  0.814  1.0
  O  O35  1  0.673  0.182  0.105  1.0
  O  O36  1  0.677  0.687  0.394  1.0
[/CIF]
.
The compound described by Li9Fe4(SiO5)4 crystallizes in the triclinic P1 space group. There are nine inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(13), one O(2), one O(6), and one O(9) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(2)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Li(7)O4 tetrahedra, corners with two equivalent Li(9)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(1), one O(10), one O(14), and one O(5) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the third Li site, Li(3) is bonded to one O(12), one O(3), one O(7), and one O(8) atom to form LiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra, corners with two equivalent Fe(3)O4 tetrahedra, corners with two equivalent Fe(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. In the fourth Li site, Li(4) is bonded to one O(10), one O(16), one O(4), and one O(5) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(2)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the fifth Li site, Li(5) is bonded to one O(12), one O(15), one O(20), and one O(3) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(3)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(9)O4 tetrahedra, corners with two equivalent Fe(4)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. In the sixth Li site, Li(6) is bonded to one O(11), one O(16), one O(19), and one O(4) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(4)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, corners with two equivalent Fe(3)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. In the seventh Li site, Li(7) is bonded to one O(13), one O(17), one O(18), and one O(2) atom to form LiO4 tetrahedra that share  a cornercorner with one Li(9)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the eighth Li site, Li(8) is bonded to one O(14), one O(16), one O(19), and one O(5) atom to form LiO4 tetrahedra that share  a cornercorner with one Fe(3)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the ninth Li site, Li(9) is bonded to one O(13), one O(15), one O(20), and one O(6) atom to form LiO4 tetrahedra that share  a cornercorner with one Li(7)O4 tetrahedra,  a cornercorner with one Fe(4)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(17), one O(2), and one O(9) atom to form FeO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(7)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(10), one O(18), and one O(2) atom to form FeO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra,  a cornercorner with one Li(4)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(7)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. In the third Fe site, Fe(3) is bonded to one O(11), one O(12), one O(19), and one O(7) atom to form FeO4 tetrahedra that share  a cornercorner with one Li(5)O4 tetrahedra,  a cornercorner with one Li(8)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, corners with two equivalent Fe(4)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. In the fourth Fe site, Fe(4) is bonded to one O(11), one O(12), one O(20), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Li(6)O4 tetrahedra,  a cornercorner with one Li(9)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra, corners with two equivalent Fe(3)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(19), one O(4), one O(5), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(6)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, and corners with two equivalent Fe(3)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(20), one O(3), one O(6), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra, corners with two equivalent Li(9)O4 tetrahedra, and corners with two equivalent Fe(4)O4 tetrahedra. In the third Si site, Si(3) is bonded to one O(13), one O(15), one O(17), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Li(5)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(7)O4 tetrahedra, corners with two equivalent Li(9)O4 tetrahedra, and corners with two equivalent Fe(1)O4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(10), one O(14), one O(16), and one O(18) atom to form SiO4 tetrahedra that share  a cornercorner with one Li(6)O4 tetrahedra,  a cornercorner with one Li(7)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Li(8)O4 tetrahedra, and corners with two equivalent Fe(2)O4 tetrahedra. There are twenty inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(2), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded to one Li(1), one Li(7), one Fe(1), and one Fe(2) atom to form OLi2Fe2 tetrahedra that share  a cornercorner with one O(10)Li2FeSi tetrahedra and corners with two equivalent O(13)Li3Si tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(3), one Li(5), and one Si(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(4), one Li(6), and one Si(1) atom. In the fifth O site, O(5) is bonded to one Li(2), one Li(4), one Li(8), and one Si(1) atom to form OLi3Si tetrahedra that share corners with two equivalent O(10)Li2FeSi tetrahedra, corners with two equivalent O(19)Li2FeSi tetrahedra, and corners with two equivalent O(16)Li3Si tetrahedra. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Li(1), one Li(9), and one Si(2) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Li(3), one Fe(3), and one Si(1) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Li(3), one Fe(4), and one Si(2) atom. In the ninth O site, O(9) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(3) atom. In the tenth O site, O(10) is bonded to one Li(2), one Li(4), one Fe(2), and one Si(4) atom to form OLi2FeSi tetrahedra that share  a cornercorner with one O(2)Li2Fe2 tetrahedra, corners with two equivalent O(16)Li3Si tetrahedra, and corners with two equivalent O(5)Li3Si tetrahedra. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Li(6), one Fe(3), and one Fe(4) atom. In the twelfth O site, O(12) is bonded to one Li(3), one Li(5), one Fe(3), and one Fe(4) atom to form corner-sharing OLi2Fe2 tetrahedra. In the thirteenth O site, O(13) is bonded to one Li(1), one Li(7), one Li(9), and one Si(3) atom to form distorted OLi3Si tetrahedra that share  a cornercorner with one O(20)Li2FeSi tetrahedra and corners with two equivalent O(2)Li2Fe2 tetrahedra. In the fourteenth O site, O(14) is bonded in a trigonal planar geometry to one Li(2), one Li(8), and one Si(4) atom. In the fifteenth O site, O(15) is bonded in a trigonal planar geometry to one Li(5), one Li(9), and one Si(3) atom. In the sixteenth O site, O(16) is bonded to one Li(4), one Li(6), one Li(8), and one Si(4) atom to form OLi3Si tetrahedra that share corners with two equivalent O(10)Li2FeSi tetrahedra, corners with two equivalent O(19)Li2FeSi tetrahedra, and corners with two equivalent O(5)Li3Si tetrahedra. In the seventeenth O site, O(17) is bonded in a trigonal planar geometry to one Li(7), one Fe(1), and one Si(3) atom. In the eighteenth O site, O(18) is bonded in a trigonal planar geometry to one Li(7), one Fe(2), and one Si(4) atom. In the nineteenth O site, O(19) is bonded to one Li(6), one Li(8), one Fe(3), and one Si(1) atom to form OLi2FeSi tetrahedra that share  a cornercorner with one O(12)Li2Fe2 tetrahedra, corners with two equivalent O(16)Li3Si tetrahedra, and corners with two equivalent O(5)Li3Si tetrahedra. In the twentieth O site, O(20) is bonded to one Li(5), one Li(9), one Fe(4), and one Si(2) atom to form OLi2FeSi tetrahedra that share  a cornercorner with one O(13)Li3Si tetrahedra and corners with two equivalent O(12)Li2Fe2 tetrahedra. is represented by the CIF file [CIF]
data_Li9Fe4(SiO5)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.013
_cell_length_b   5.618
_cell_length_c   16.184
_cell_angle_alpha   90.288
_cell_angle_beta   89.978
_cell_angle_gamma   89.639
_symmetry_Int_Tables_number   1
_cell_volume   455.754
_cell_formula_units_Z   1
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  0.994  0.662  0.599  1.0
  Li  Li1  1  0.998  0.166  0.909  1.0
  Li  Li2  1  0.001  0.171  0.301  1.0
  Li  Li3  1  0.997  0.659  0.002  1.0
  Li  Li4  1  0.498  0.337  0.403  1.0
  Li  Li5  1  0.502  0.831  0.092  1.0
  Li  Li6  1  0.510  0.825  0.696  1.0
  Li  Li7  1  0.497  0.339  0.997  1.0
  Li  Li8  1  0.502  0.836  0.506  1.0
  Fe  Fe9  1  0.001  0.169  0.702  1.0
  Fe  Fe10  1  0.007  0.667  0.802  1.0
  Fe  Fe11  1  0.503  0.333  0.199  1.0
  Fe  Fe12  1  0.504  0.836  0.301  1.0
  Si  Si13  1  0.005  0.168  0.096  1.0
  Si  Si14  1  0.009  0.671  0.400  1.0
  Si  Si15  1  0.500  0.338  0.599  1.0
  Si  Si16  1  0.508  0.830  0.903  1.0
  O  O17  1  0.058  0.336  0.801  1.0
  O  O18  1  0.107  0.842  0.706  1.0
  O  O19  1  0.121  0.405  0.381  1.0
  O  O20  1  0.110  0.895  0.081  1.0
  O  O21  1  0.103  0.323  0.017  1.0
  O  O22  1  0.116  0.753  0.491  1.0
  O  O23  1  0.133  0.261  0.185  1.0
  O  O24  1  0.133  0.852  0.330  1.0
  O  O25  1  0.174  0.344  0.619  1.0
  O  O26  1  0.176  0.816  0.895  1.0
  O  O27  1  0.556  0.663  0.202  1.0
  O  O28  1  0.608  0.161  0.295  1.0
  O  O29  1  0.609  0.610  0.601  1.0
  O  O30  1  0.609  0.104  0.918  1.0
  O  O31  1  0.531  0.193  0.510  1.0
  O  O32  1  0.606  0.674  0.983  1.0
  O  O33  1  0.637  0.162  0.670  1.0
  O  O34  1  0.635  0.736  0.814  1.0
  O  O35  1  0.673  0.182  0.105  1.0
  O  O36  1  0.677  0.687  0.394  1.0
[/CIF]
.