Materials Data on Ba3Al2F12 by Materials Project

Abstract

Ba3Al2F12 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to eleven F1- atoms. There are a spread of Ba–F bond distances ranging from 2.71–3.09 Å. In the second Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of Ba–F bond distances ranging from 2.63–3.02 Å. In the third Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to ten F1- atoms. There are a spread of Ba–F bond distances ranging from 2.75–2.85 Å. Al3+ is bonded to six F1- atoms to form corner-sharing AlF6 octahedra. The corner-sharing octahedra tilt angles range from 31–34°. There are a spread of Al–F bond distances ranging from 1.79–1.88 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to three Ba2+ and one Al3+ atom. In the second F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Al3+ atoms. In the third F1- site, F1- is bonded in a bent 150 degrees geometry to one Ba2+ and two equivalent Al3+ atoms. In the fourth F1- site, F1- is bonded to four Ba2+ atoms to form a mixture of corner and edge-sharing FBa4 tetrahedra. In the fifth F1- site, F1- is bonded in a distorted single-bond geometry to two Ba2+ and one Al3+ atom. In the sixth F1- site, F1- is bonded to four Ba2+ atoms to form a mixture of corner and edge-sharing FBa4 tetrahedra. In the seventh F1- site, F1- is bonded in a distorted single-bond geometry to three Ba2+ and one Al3+ atom. In the eighth F1- site, F1- is bonded in a distorted single-bond geometry to three Ba2+ and one Al3+ atom.