LiFeSi3O8 crystallizes in the triclinic P-1 space group. Li(1) is bonded to one O(1), one O(4), one O(5), and two equivalent O(6) atoms to form distorted LiO5 trigonal bipyramids that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, edges with two equivalent Fe(1)O4 tetrahedra, and  an edgeedge with one Li(1)O5 trigonal bipyramid. 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  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with two equivalent Li(1)O5 trigonal bipyramids. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, and corners with two equivalent Li(1)O5 trigonal bipyramids. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Li(1)O5 trigonal bipyramids. In the third Si site, Si(3) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Li(1)O5 trigonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(1), one Fe(1), and one Si(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate 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(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Li(1), one Fe(1), and one Si(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Fe(1) and one Si(2) atom.
LiFeSi3O8 crystallizes in the triclinic P-1 space group. Li(1) is bonded to one O(1), one O(4), one O(5), and two equivalent O(6) atoms to form distorted LiO5 trigonal bipyramids that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, edges with two equivalent Fe(1)O4 tetrahedra, and  an edgeedge with one Li(1)O5 trigonal bipyramid. The Li(1)-O(1) bond length is 2.47 Å. The Li(1)-O(4) bond length is 2.44 Å. The Li(1)-O(5) bond length is 2.13 Å. There is one shorter (2.30 Å) and one longer (2.38 Å) Li(1)-O(6) bond length. 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  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and edges with two equivalent Li(1)O5 trigonal bipyramids. The Fe(1)-O(1) bond length is 1.88 Å. The Fe(1)-O(4) bond length is 1.88 Å. The Fe(1)-O(6) bond length is 1.92 Å. The Fe(1)-O(8) bond length is 1.86 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, and corners with two equivalent Li(1)O5 trigonal bipyramids. The Si(1)-O(1) bond length is 1.62 Å. The Si(1)-O(3) bond length is 1.63 Å. The Si(1)-O(5) bond length is 1.66 Å. The Si(1)-O(7) bond length is 1.63 Å. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, and corners with two equivalent Li(1)O5 trigonal bipyramids. The Si(2)-O(2) bond length is 1.63 Å. The Si(2)-O(4) bond length is 1.63 Å. The Si(2)-O(5) bond length is 1.68 Å. The Si(2)-O(8) bond length is 1.62 Å. In the third Si site, Si(3) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and corners with two equivalent Li(1)O5 trigonal bipyramids. The Si(3)-O(2) bond length is 1.62 Å. The Si(3)-O(3) bond length is 1.63 Å. The Si(3)-O(6) bond length is 1.63 Å. The Si(3)-O(7) bond length is 1.64 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(1), one Fe(1), and one Si(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate 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(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Li(1), one Fe(1), and one Si(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Fe(1) and one Si(2) atom.