Materials Data on Ba5Al3F19 by Materials Project

Ba5Al3F19 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to eleven F1- atoms. There are a spread of Ba–F bond distances ranging from 2.68–3.33 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 2.53–3.16 Å. In the third Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are four shorter (2.68 Å) and four longer (2.82 Å) Ba–F bond lengths. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of Al–F bond distances ranging from 1.81–1.85 Å. In the second Al3+ site, Al3+ is bonded to six F1- atoms to form corner-sharing AlF6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Al–F bond distances ranging from 1.81–1.91 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 to four Ba2+ atoms to form a mixture of distorted edge and corner-sharing FBa4 tetrahedra. In the third F1- site, F1- is bonded in a linear geometry to two equivalent Al3+ atoms. In the fourth F1- site, F1- is bonded in a linear geometry to two equivalent Al3+ atoms. 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 in a distorted single-bond geometry to three Ba2+ and one Al3+ atom. In the seventh F1- site, F1- is bonded in a distorted single-bond geometry to two 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.