Li2MnF4 is beta indium sulfide-derived structured and crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one F(2) and three equivalent F(1) atoms to form LiF4 trigonal pyramids that share corners with three equivalent Mn(1)F6 octahedra, corners with four equivalent Li(1)F4 trigonal pyramids,  an edgeedge with one Mn(1)F6 octahedra, and  an edgeedge with one Li(1)F4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 51-59°. Mn(1) is bonded to two equivalent F(1) and four equivalent F(2) atoms to form MnF6 octahedra that share corners with four equivalent Mn(1)F6 octahedra, corners with six equivalent Li(1)F4 trigonal pyramids, and edges with two equivalent Li(1)F4 trigonal pyramids. The corner-sharing octahedral tilt angles are 41°. There are two inequivalent F sites. In the first F site, F(1) is bonded to three equivalent Li(1) and one Mn(1) atom to form a mixture of distorted corner and edge-sharing FLi3Mn trigonal pyramids. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Li(1) and two equivalent Mn(1) atoms.
Li2MnF4 is beta indium sulfide-derived structured and crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one F(2) and three equivalent F(1) atoms to form LiF4 trigonal pyramids that share corners with three equivalent Mn(1)F6 octahedra, corners with four equivalent Li(1)F4 trigonal pyramids,  an edgeedge with one Mn(1)F6 octahedra, and  an edgeedge with one Li(1)F4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 51-59°. The Li(1)-F(2) bond length is 1.89 Å. There are a spread of Li(1)-F(1) bond distances ranging from 1.86-1.96 Å. Mn(1) is bonded to two equivalent F(1) and four equivalent F(2) atoms to form MnF6 octahedra that share corners with four equivalent Mn(1)F6 octahedra, corners with six equivalent Li(1)F4 trigonal pyramids, and edges with two equivalent Li(1)F4 trigonal pyramids. The corner-sharing octahedral tilt angles are 41°. Both Mn(1)-F(1) bond lengths are 2.20 Å. There are two shorter (2.13 Å) and two longer (2.17 Å) Mn(1)-F(2) bond lengths. There are two inequivalent F sites. In the first F site, F(1) is bonded to three equivalent Li(1) and one Mn(1) atom to form a mixture of distorted corner and edge-sharing FLi3Mn trigonal pyramids. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Li(1) and two equivalent Mn(1) atoms.