Materials Data on Li2BeF4 by Materials Project
Li2BeF4 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with four LiF4 tetrahedra and corners with four equivalent BeF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.89–1.91 Å. In the second Li1+ site, Li1+ is bonded to four F1- atoms to form LiF4 tetrahedra that share corners with four LiF4 tetrahedra and corners with four equivalent BeF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.89–1.93 Å. Be2+ is bonded to four F1- atoms to form BeF4 tetrahedra that share corners with eight LiF4 tetrahedra. There is three shorter (1.57 Å) and one longer (1.58 Å) Be–F bond length. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Be2+ atom. In the second F1- site, F1- is bonded in a trigonal planar geometry to two Li1+ and one Be2+ atom. In the third F1- site, F1- is bonded in a trigonal planar geometry to two equivalent Li1+ and one Be2+ atom. In the fourth F1- site, F1- is bonded in a trigonal planar geometry to two equivalent Li1+ and one Be2+ atom.