Materials Data on CsAlF4 by Materials Project

Abstract

CsAlF4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Cs–F bond distances ranging from 3.08–3.52 Å. In the second Cs1+ site, Cs1+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of Cs–F bond distances ranging from 2.99–3.44 Å. In the third Cs1+ site, Cs1+ is bonded in a 2-coordinate geometry to ten F1- atoms. There are a spread of Cs–F bond distances ranging from 2.96–3.65 Å. There are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six F1- atoms to form corner-sharing AlF6 octahedra. The corner-sharing octahedra tilt angles range from 32–36°. There are a spread of Al–F bond distances ranging from 1.77–1.92 Å. In the second Al3+ site, Al3+ is bonded to six F1- atoms to form corner-sharing AlF6 octahedra. The corner-sharing octahedra tilt angles range from 32–36°. There are a spread of Al–F bond distances ranging from 1.77–1.93 Å. In the third Al3+ site, Al3+ is bonded to six F1- atoms to form corner-sharing AlF6 octahedra. The corner-sharing octahedra tilt angles range from 36–42°. There is four shorter (1.81 Å) and two longer (1.84 Å) Al–F bond length. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to four Cs1+ and one Al3+ atom. In the second F1- site, F1- is bonded in a bent 150 degrees geometry to two Al3+ atoms. In the third F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Cs1+ and two equivalent Al3+ atoms. In the fourth F1- site, F1- is bonded in a bent 150 degrees geometry to one Cs1+ and two Al3+ atoms. In the fifth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Cs1+ and two Al3+ atoms. In the sixth F1- site, F1- is bonded in a distorted single-bond geometry to three Cs1+ and one Al3+ atom. In the seventh F1- site, F1- is bonded in a distorted single-bond geometry to four Cs1+ and one Al3+ atom. In the eighth F1- site, F1- is bonded in a distorted single-bond geometry to four Cs1+ and one Al3+ atom.