Li2BeF4 crystallizes in the trigonal R-3 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(3), one F(4), and two equivalent F(2) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(1)F4 tetrahedra, corners with two equivalent Li(2)F4 tetrahedra, and corners with four equivalent Be(1)F4 tetrahedra. In the second Li site, Li(2) is bonded to one F(3), one F(4), and two equivalent F(1) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(1)F4 tetrahedra, corners with two equivalent Li(2)F4 tetrahedra, and corners with four equivalent Be(1)F4 tetrahedra. Be(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form BeF4 tetrahedra that share corners with four equivalent Li(1)F4 tetrahedra and corners with four equivalent Li(2)F4 tetrahedra. There are four inequivalent F sites. In the first F site, F(3) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Be(1) atom. In the second F site, F(4) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Be(1) atom. In the third F site, F(1) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Be(1) atom. In the fourth F site, F(2) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Be(1) atom.
Li2BeF4 crystallizes in the trigonal R-3 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(3), one F(4), and two equivalent F(2) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(1)F4 tetrahedra, corners with two equivalent Li(2)F4 tetrahedra, and corners with four equivalent Be(1)F4 tetrahedra. The Li(1)-F(3) bond length is 1.83 Å. The Li(1)-F(4) bond length is 1.85 Å. There is one shorter (1.84 Å) and one longer (1.85 Å) Li(1)-F(2) bond length. In the second Li site, Li(2) is bonded to one F(3), one F(4), and two equivalent F(1) atoms to form LiF4 tetrahedra that share corners with two equivalent Li(1)F4 tetrahedra, corners with two equivalent Li(2)F4 tetrahedra, and corners with four equivalent Be(1)F4 tetrahedra. The Li(2)-F(3) bond length is 1.84 Å. The Li(2)-F(4) bond length is 1.84 Å. Both Li(2)-F(1) bond lengths are 1.87 Å. Be(1) is bonded to one F(1), one F(2), one F(3), and one F(4) atom to form BeF4 tetrahedra that share corners with four equivalent Li(1)F4 tetrahedra and corners with four equivalent Li(2)F4 tetrahedra. The Be(1)-F(1) bond length is 1.56 Å. The Be(1)-F(2) bond length is 1.55 Å. The Be(1)-F(3) bond length is 1.55 Å. The Be(1)-F(4) bond length is 1.56 Å. There are four inequivalent F sites. In the first F site, F(3) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Be(1) atom. In the second F site, F(4) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Be(1) atom. In the third F site, F(1) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Be(1) atom. In the fourth F site, F(2) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Be(1) atom.