Li2Mn3F8 crystallizes in the tetragonal I4_1/a space group. Li(1) is bonded to one F(1), one F(3), two equivalent F(2), and two equivalent F(4) atoms to form distorted LiF6 octahedra that share corners with two equivalent Li(1)F6 octahedra, corners with two equivalent Mn(2)F4 tetrahedra, and  an edgeedge with one Li(1)F6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 7-coordinate geometry to one F(2), two equivalent F(1), two equivalent F(3), and two equivalent F(4) atoms. In the second Mn site, Mn(2) is bonded to four equivalent F(2) atoms to form MnF4 tetrahedra that share corners with eight equivalent Li(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 62-72°. In the third Mn site, Mn(3) is bonded in a distorted body-centered cubic geometry to four equivalent F(1) and four equivalent F(3) atoms. There are four inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to one Li(1), one Mn(3), and two equivalent Mn(1) atoms. In the second F site, F(2) is bonded to two equivalent Li(1), one Mn(1), and one Mn(2) atom to form distorted FLi2Mn2 tetrahedra that share corners with three equivalent F(2)Li2Mn2 tetrahedra, corners with four equivalent F(4)Li2Mn2 tetrahedra, corners with four equivalent F(3)LiMn3 tetrahedra,  an edgeedge with one F(2)Li2Mn2 tetrahedra, and  an edgeedge with one F(4)Li2Mn2 tetrahedra. In the third F site, F(3) is bonded to one Li(1), one Mn(3), and two equivalent Mn(1) atoms to form distorted FLiMn3 tetrahedra that share corners with three equivalent F(3)LiMn3 tetrahedra, corners with four equivalent F(2)Li2Mn2 tetrahedra, corners with four equivalent F(4)Li2Mn2 tetrahedra,  an edgeedge with one F(4)Li2Mn2 tetrahedra, and  an edgeedge with one F(3)LiMn3 tetrahedra. In the fourth F site, F(4) is bonded to two equivalent Li(1) and two equivalent Mn(1) atoms to form distorted FLi2Mn2 tetrahedra that share corners with four equivalent F(2)Li2Mn2 tetrahedra, corners with four equivalent F(3)LiMn3 tetrahedra,  an edgeedge with one F(2)Li2Mn2 tetrahedra,  an edgeedge with one F(3)LiMn3 tetrahedra, and edges with two equivalent F(4)Li2Mn2 tetrahedra.
Li2Mn3F8 crystallizes in the tetragonal I4_1/a space group. Li(1) is bonded to one F(1), one F(3), two equivalent F(2), and two equivalent F(4) atoms to form distorted LiF6 octahedra that share corners with two equivalent Li(1)F6 octahedra, corners with two equivalent Mn(2)F4 tetrahedra, and  an edgeedge with one Li(1)F6 octahedra. The corner-sharing octahedral tilt angles are 50°. The Li(1)-F(1) bond length is 2.10 Å. The Li(1)-F(3) bond length is 2.14 Å. There is one shorter (2.05 Å) and one longer (2.37 Å) Li(1)-F(2) bond length. There is one shorter (1.98 Å) and one longer (2.06 Å) Li(1)-F(4) bond length. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 7-coordinate geometry to one F(2), two equivalent F(1), two equivalent F(3), and two equivalent F(4) atoms. The Mn(1)-F(2) bond length is 2.28 Å. There is one shorter (2.10 Å) and one longer (2.14 Å) Mn(1)-F(1) bond length. There is one shorter (2.16 Å) and one longer (2.52 Å) Mn(1)-F(3) bond length. There is one shorter (2.19 Å) and one longer (2.22 Å) Mn(1)-F(4) bond length. In the second Mn site, Mn(2) is bonded to four equivalent F(2) atoms to form MnF4 tetrahedra that share corners with eight equivalent Li(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 62-72°. All Mn(2)-F(2) bond lengths are 2.02 Å. In the third Mn site, Mn(3) is bonded in a distorted body-centered cubic geometry to four equivalent F(1) and four equivalent F(3) atoms. All Mn(3)-F(1) bond lengths are 2.54 Å. All Mn(3)-F(3) bond lengths are 2.15 Å. There are four inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to one Li(1), one Mn(3), and two equivalent Mn(1) atoms. In the second F site, F(2) is bonded to two equivalent Li(1), one Mn(1), and one Mn(2) atom to form distorted FLi2Mn2 tetrahedra that share corners with three equivalent F(2)Li2Mn2 tetrahedra, corners with four equivalent F(4)Li2Mn2 tetrahedra, corners with four equivalent F(3)LiMn3 tetrahedra,  an edgeedge with one F(2)Li2Mn2 tetrahedra, and  an edgeedge with one F(4)Li2Mn2 tetrahedra. In the third F site, F(3) is bonded to one Li(1), one Mn(3), and two equivalent Mn(1) atoms to form distorted FLiMn3 tetrahedra that share corners with three equivalent F(3)LiMn3 tetrahedra, corners with four equivalent F(2)Li2Mn2 tetrahedra, corners with four equivalent F(4)Li2Mn2 tetrahedra,  an edgeedge with one F(4)Li2Mn2 tetrahedra, and  an edgeedge with one F(3)LiMn3 tetrahedra. In the fourth F site, F(4) is bonded to two equivalent Li(1) and two equivalent Mn(1) atoms to form distorted FLi2Mn2 tetrahedra that share corners with four equivalent F(2)Li2Mn2 tetrahedra, corners with four equivalent F(3)LiMn3 tetrahedra,  an edgeedge with one F(2)Li2Mn2 tetrahedra,  an edgeedge with one F(3)LiMn3 tetrahedra, and edges with two equivalent F(4)Li2Mn2 tetrahedra.