Materials Data on Rb2NaAl3F12 by Materials Project
Rb2NaAl3F12 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 7-coordinate geometry to seven F1- atoms. There are a spread of Rb–F bond distances ranging from 2.92–3.09 Å. In the second Rb1+ site, Rb1+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Rb–F bond distances ranging from 2.78–3.22 Å. Na1+ is bonded to six F1- atoms to form distorted NaF6 octahedra that share corners with six AlF6 octahedra. The corner-sharing octahedra tilt angles range from 50–65°. There are a spread of Na–F bond distances ranging from 2.28–2.38 Å. There are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six F1- atoms to form AlF6 octahedra that share corners with two equivalent NaF6 octahedra and corners with four AlF6 octahedra. The corner-sharing octahedra tilt angles range from 35–65°. There are a spread of Al–F bond distances ranging from 1.77–1.87 Å. In the second Al3+ site, Al3+ is bonded to six F1- atoms to form AlF6 octahedra that share corners with two equivalent NaF6 octahedra and corners with four AlF6 octahedra. The corner-sharing octahedra tilt angles range from 34–56°. There are a spread of Al–F bond distances ranging from 1.78–1.87 Å. In the third Al3+ site, Al3+ is bonded to six F1- atoms to form AlF6 octahedra that share corners with two equivalent NaF6 octahedra and corners with four AlF6 octahedra. The corner-sharing octahedra tilt angles range from 34–60°. There are a spread of Al–F bond distances ranging from 1.76–1.87 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a bent 150 degrees geometry to one Rb1+ and two Al3+ atoms. 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 distorted trigonal planar geometry to one Rb1+, one Na1+, and one Al3+ atom. In the fourth F1- site, F1- is bonded in a distorted bent 150 degrees geometry to one Rb1+ and two equivalent Al3+ atoms. In the fifth F1- site, F1- is bonded in a 2-coordinate geometry to one Rb1+, one Na1+, and one Al3+ atom. In the sixth F1- site, F1- is bonded in a 1-coordinate geometry to two Rb1+, one Na1+, and one Al3+ atom. In the seventh F1- site, F1- is bonded in a bent 150 degrees geometry to one Rb1+ and two Al3+ atoms. In the eighth F1- site, F1- is bonded in a 1-coordinate geometry to two equivalent Rb1+, one Na1+, and one Al3+ atom.