Li3Mn2(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 Mn(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Mn(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 Mn(1)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. Mn(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form MnO4 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(1) and two equivalent O(2) atoms to form SiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Mn(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(3) 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 Mn(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Li(1), one Mn(1), and one Si(1) atom. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Mn(1), and one Si(1) atom to form edge-sharing OLi2MnSi tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Mn(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Mn(1), and one Si(2) atom.
Li3Mn2(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 Mn(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Mn(1)O4 tetrahedra. The Li(1)-O(1) bond length is 2.01 Å. The Li(1)-O(2) bond length is 2.00 Å. The Li(1)-O(3) bond length is 1.91 Å. The Li(1)-O(4) bond length is 2.07 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 Mn(1)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. Both Li(2)-O(2) bond lengths are 2.09 Å. Both Li(2)-O(4) bond lengths are 2.08 Å. Mn(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form MnO4 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 Mn(1)-O(1) bond length is 1.97 Å. The Mn(1)-O(2) bond length is 2.05 Å. The Mn(1)-O(3) bond length is 1.96 Å. The Mn(1)-O(4) bond length is 2.08 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form SiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Mn(1)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. Both Si(1)-O(1) bond lengths are 1.64 Å. Both Si(1)-O(2) bond lengths are 1.66 Å. In the second Si site, Si(2) is bonded to two equivalent O(3) 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 Mn(1)O4 tetrahedra. Both Si(2)-O(3) 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 distorted trigonal planar geometry to one Li(1), one Mn(1), and one Si(1) atom. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Mn(1), and one Si(1) atom to form edge-sharing OLi2MnSi tetrahedra. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Mn(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Mn(1), and one Si(2) atom.