Materials Data on Cs2NaCrF6 by Materials Project

Abstract

Cs2NaCrF6 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded to twelve F1- atoms to form distorted CsF12 cuboctahedra that share corners with nine CsF12 cuboctahedra, corners with three equivalent CrF6 octahedra, faces with seven CsF12 cuboctahedra, faces with three equivalent CrF6 octahedra, and faces with four equivalent NaF6 octahedra. The corner-sharing octahedral tilt angles are 12°. There are a spread of Cs–F bond distances ranging from 3.19–3.40 Å. In the second Cs1+ site, Cs1+ is bonded to twelve F1- atoms to form distorted CsF12 cuboctahedra that share corners with nine CsF12 cuboctahedra, corners with three equivalent NaF6 octahedra, faces with seven CsF12 cuboctahedra, faces with three equivalent NaF6 octahedra, and faces with four CrF6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are a spread of Cs–F bond distances ranging from 3.18–3.28 Å. Na1+ is bonded to six F1- atoms to form distorted NaF6 octahedra that share corners with three equivalent CsF12 cuboctahedra, corners with three equivalent CrF6 octahedra, faces with seven CsF12 cuboctahedra, and a faceface with one CrF6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are three shorter (2.30 Å) and three longer (2.40 Å) Na–F bond lengths. There are two inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six equivalent F1- atoms to form CrF6 octahedra that share corners with six equivalent NaF6 octahedra and faces with eight CsF12 cuboctahedra. The corner-sharing octahedral tilt angles are 8°. All Cr–F bond lengths are 1.97 Å. In the second Cr3+ site, Cr3+ is bonded to six equivalent F1- atoms to form CrF6 octahedra that share corners with six equivalent CsF12 cuboctahedra, faces with six equivalent CsF12 cuboctahedra, and faces with two equivalent NaF6 octahedra. All Cr–F bond lengths are 1.96 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted linear geometry to four Cs1+, one Na1+, and one Cr3+ atom. In the second F1- site, F1- is bonded in a 2-coordinate geometry to four Cs1+, one Na1+, and one Cr3+ atom.