DOI: 10.17188/1718514
title: Materials Data on KBaNa2Ti3Fe(Si2O9)2 by Materials Project

description: KNa2BaTi3Fe(Si2O9)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. K1+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.78–3.10 Å. There are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with four SiO4 tetrahedra, corners with two TiO5 trigonal bipyramids, edges with two equivalent NaO6 octahedra, edges with two equivalent TiO6 octahedra, and edges with two equivalent FeO6 octahedra. There are a spread of Na–O bond distances ranging from 2.33–2.53 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two SiO4 tetrahedra, corners with two TiO5 trigonal bipyramids, edges with two equivalent NaO6 octahedra, edges with two equivalent TiO6 octahedra, and edges with two equivalent FeO6 octahedra. There are a spread of Na–O bond distances ranging from 2.34–2.54 Å. Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.78–3.01 Å. There are three inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share a cornercorner with one FeO6 octahedra, corners with two NaO6 octahedra, and corners with four SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–67°. There are a spread of Ti–O bond distances ranging from 1.74–1.99 Å. In the second Ti4+ site, Ti4+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share a cornercorner with one FeO6 octahedra, corners with two NaO6 octahedra, and corners with four SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–68°. There are a spread of Ti–O bond distances ranging from 1.74–2.00 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four SiO4 tetrahedra, edges with two equivalent FeO6 octahedra, and edges with four NaO6 octahedra. There are a spread of Ti–O bond distances ranging from 1.87–2.22 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two SiO4 tetrahedra, corners with two TiO5 trigonal bipyramids, edges with two equivalent TiO6 octahedra, and edges with four NaO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.93–2.21 Å. There are four inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one TiO6 octahedra, corners with two NaO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with two equivalent TiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 50–65°. There is three shorter (1.63 Å) and one longer (1.68 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, a cornercorner with one TiO6 octahedra, a cornercorner with one FeO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with two equivalent TiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 51–63°. There are a spread of Si–O bond distances ranging from 1.63–1.68 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, a cornercorner with one TiO6 octahedra, a cornercorner with one FeO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with two equivalent TiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 50–64°. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one TiO6 octahedra, corners with two NaO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with two equivalent TiO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 50–65°. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ti4+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, one Ti4+, one Fe3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Na1+, one Ti4+, one Fe3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ti4+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Ti4+, and one Fe3+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Ti4+, and one Fe3+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two Si4+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ and two Si4+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ba2+, one Ti4+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ba2+, one Ti4+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ba2+, one Ti4+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ba2+, one Ti4+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ti4+, and one Fe3+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Ti4+, and one Fe3+ atom. In the fifteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ba2+, one Ti4+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ba2+, one Ti4+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Ba2+, one Ti4+, and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Ba2+, one Ti4+, and one Si4+ atom.