Li3Fe2(SiO4)2 is Clathrate-derived structured and crystallizes in the monoclinic C2 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form 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(1)O4 tetrahedra. In the second Li site, Li(2) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Si(2)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Fe(1)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)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 two equivalent O(2) and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Fe(1)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. In the second Si site, Si(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, and corners with four equivalent Fe(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(2) atom. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(1) atom to form a mixture of corner and edge-sharing OLi2FeSi trigonal pyramids. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one Si(1) atom. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(2) atom to form distorted corner-sharing OLi2FeSi tetrahedra.
Li3Fe2(SiO4)2 is Clathrate-derived structured and crystallizes in the monoclinic C2 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form 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(1)O4 tetrahedra. The Li(1)-O(1) bond length is 1.92 Å. The Li(1)-O(2) bond length is 2.01 Å. The Li(1)-O(3) bond length is 2.01 Å. The Li(1)-O(4) bond length is 2.10 Å. In the second Li site, Li(2) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Si(2)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Fe(1)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. Both Li(2)-O(2) bond lengths are 2.08 Å. Both Li(2)-O(4) bond lengths are 2.04 Å. Fe(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form FeO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)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. The Fe(1)-O(1) bond length is 1.91 Å. The Fe(1)-O(2) bond length is 1.99 Å. The Fe(1)-O(3) bond length is 1.95 Å. The Fe(1)-O(4) bond length is 2.01 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form SiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Fe(1)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. Both Si(1)-O(2) bond lengths are 1.67 Å. Both Si(1)-O(3) bond lengths are 1.63 Å. In the second Si site, Si(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, and corners with four equivalent Fe(1)O4 tetrahedra. Both Si(2)-O(1) bond lengths are 1.64 Å. Both Si(2)-O(4) bond lengths are 1.67 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(1), one Fe(1), and one Si(2) atom. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(1) atom to form a mixture of corner and edge-sharing OLi2FeSi trigonal pyramids. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one Si(1) atom. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Fe(1), and one Si(2) atom to form distorted corner-sharing OLi2FeSi tetrahedra.