DOI: 10.17188/1475733
title: Materials Data on KNa7V6Cr2O24 by Materials Project

description: KNa7V6Cr2O24 is (Cubic) Perovskite-derived structured and crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. K1+ is bonded to twelve O2- atoms to form KO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six VO6 octahedra. There are seven shorter (2.69 Å) and five longer (2.70 Å) K–O bond lengths. There are five inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with two equivalent KO12 cuboctahedra, faces with four NaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six VO6 octahedra. There are five shorter (2.67 Å) and seven longer (2.68 Å) Na–O bond lengths. In the second Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with four equivalent KO12 cuboctahedra, corners with eight NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six VO6 octahedra. There are a spread of Na–O bond distances ranging from 2.65–2.68 Å. In the third Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with two equivalent KO12 cuboctahedra, faces with four equivalent NaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six VO6 octahedra. There are three shorter (2.67 Å) and nine longer (2.68 Å) Na–O bond lengths. In the fourth Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with four equivalent KO12 cuboctahedra, corners with eight equivalent NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six VO6 octahedra. There are four shorter (2.65 Å) and eight longer (2.68 Å) Na–O bond lengths. In the fifth Na1+ site, Na1+ is bonded to twelve O2- atoms to form NaO12 cuboctahedra that share corners with twelve NaO12 cuboctahedra, faces with six NaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six VO6 octahedra. All Na–O bond lengths are 2.67 Å. There are two inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share corners with two equivalent CrO6 octahedra, corners with four VO6 octahedra, a faceface with one KO12 cuboctahedra, and faces with seven NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of V–O bond distances ranging from 1.87–1.90 Å. In the second V5+ site, V5+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six VO6 octahedra, a faceface with one KO12 cuboctahedra, and faces with seven NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of V–O bond distances ranging from 1.88–1.90 Å. Cr5+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent CrO6 octahedra, corners with four equivalent VO6 octahedra, a faceface with one KO12 cuboctahedra, and faces with seven NaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Cr–O bond distances ranging from 1.89–1.91 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to one K1+, three Na1+, one V5+, and one Cr5+ atom. In the second O2- site, O2- is bonded in a distorted linear geometry to one K1+, three Na1+, and two V5+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four Na1+, one V5+, and one Cr5+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two V5+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to one K1+, three Na1+, and two equivalent Cr5+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent Cr5+ atoms. In the seventh O2- site, O2- is bonded in a distorted linear geometry to one K1+, three Na1+, and two equivalent V5+ atoms. In the eighth O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent V5+ atoms. In the ninth O2- site, O2- is bonded in a distorted linear geometry to one K1+, three Na1+, and two equivalent V5+ atoms. In the tenth O2- site, O2- is bonded in a distorted linear geometry to four Na1+ and two equivalent V5+ atoms.