DOI: 10.17188/1475791
title: Materials Data on KNa7V8O20 by Materials Project

description: KNa7V8O20 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. K1+ is bonded in a 9-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.51–2.82 Å. There are seven inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.36–2.92 Å. In the second Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.39–2.91 Å. In the third Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.37–2.92 Å. In the fourth Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.30–2.92 Å. In the fifth Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.91 Å. In the sixth Na1+ site, Na1+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.29–2.95 Å. In the seventh Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.34–2.91 Å. There are eight inequivalent V4+ sites. In the first V4+ site, V4+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four VO6 octahedra and corners with two VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 6–8°. There are a spread of V–O bond distances ranging from 1.82–2.19 Å. In the second V4+ site, V4+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four VO6 octahedra and corners with two VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 10–11°. There are a spread of V–O bond distances ranging from 1.82–2.15 Å. In the third V4+ site, V4+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four VO6 octahedra and corners with two VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 8–9°. There are a spread of V–O bond distances ranging from 1.83–2.14 Å. In the fourth V4+ site, V4+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four VO6 octahedra and corners with two VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 9–11°. There are a spread of V–O bond distances ranging from 1.82–2.13 Å. In the fifth V4+ site, V4+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two VO6 octahedra and corners with two equivalent VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–39°. There are a spread of V–O bond distances ranging from 1.77–1.87 Å. In the sixth V4+ site, V4+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two VO6 octahedra and corners with two equivalent VO4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. There are a spread of V–O bond distances ranging from 1.77–1.89 Å. In the seventh V4+ site, V4+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two VO6 octahedra and corners with two equivalent VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 30–37°. There are a spread of V–O bond distances ranging from 1.78–1.89 Å. In the eighth V4+ site, V4+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with two VO6 octahedra and corners with two equivalent VO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–37°. There are a spread of V–O bond distances ranging from 1.77–1.89 Å. There are twenty inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two equivalent V4+ atoms. In the second O2- site, O2- is bonded in a 6-coordinate geometry to one K1+, three Na1+, and two V4+ atoms. In the third O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two equivalent V4+ atoms. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to one K1+, three Na1+, and two V4+ atoms. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two equivalent V4+ atoms. In the sixth O2- site, O2- is bonded to four Na1+ and two V4+ atoms to form distorted corner-sharing ONa4V2 octahedra. In the seventh O2- site, O2- is bonded to two equivalent K1+, two equivalent Na1+, and two equivalent V4+ atoms to form distorted OK2Na2V2 octahedra that share corners with four OKNaV2 tetrahedra and faces with two equivalent OK2Na2V2 octahedra. In the eighth O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two V4+ atoms. In the ninth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent K1+, one Na1+, and two V4+ atoms. In the tenth O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Na1+ and two V4+ atoms. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, two equivalent Na1+, and two V4+ atoms. In the twelfth O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Na1+ and two V4+ atoms. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+ and two V4+ atoms. In the fourteenth O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Na1+ and two V4+ atoms. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and two V4+ atoms. In the sixteenth O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Na1+ and two V4+ atoms. In the seventeenth O2- site, O2- is bonded to one K1+, one Na1+, and two equivalent V4+ atoms to form distorted OKNaV2 tetrahedra that share corners with three ONa4V2 octahedra and corners with two equivalent OKNaV2 tetrahedra. The corner-sharing octahedra tilt angles range from 53–80°. In the eighteenth O2- site, O2- is bonded to two Na1+ and two V4+ atoms to form distorted ONa2V2 tetrahedra that share a cornercorner with one ONa4V2 octahedra and corners with two equivalent ONa2V2 tetrahedra. The corner-sharing octahedral tilt angles are 85°. In the nineteenth O2- site, O2- is bonded to two Na1+ and two equivalent V4+ atoms to form distorted ONa2V2 tetrahedra that share a cornercorner with one ONa4V2 octahedra and corners with two equivalent ONa2V2 tetrahedra. The corner-sharing octahedral tilt angles are 21°. In the twentieth O2- site, O2- is bonded to two Na1+ and two V4+ atoms to form distorted ONa2V2 tetrahedra that share corners with three ONa4V2 octahedra and corners with two equivalent ONa2V2 tetrahedra. The corner-sharing octahedra tilt angles range from 22–65°.