Materials Data on La3BeAlS7 by Materials Project
BeLa3AlS7 crystallizes in the hexagonal P6_3 space group. The structure is three-dimensional. Be2+ is bonded to six equivalent S2- atoms to form face-sharing BeS6 octahedra. There are three shorter (2.42 Å) and three longer (2.44 Å) Be–S bond lengths. La3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of La–S bond distances ranging from 2.88–3.34 Å. Al3+ is bonded in a tetrahedral geometry to four S2- atoms. There are one shorter (2.20 Å) and three longer (2.25 Å) Al–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted tetrahedral geometry to three equivalent La3+ and one Al3+ atom. In the second S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent La3+ and one Al3+ atom. In the third S2- site, S2- is bonded in a 6-coordinate geometry to two equivalent Be2+ and four equivalent La3+ atoms.