Materials Data on RbTi3NbO9 by Materials Project

Abstract

RbTi3NbO9 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. Rb1+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Rb–O bond distances ranging from 2.96–3.32 Å. There are three inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.78–2.35 Å. In the second Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.76–2.37 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share a cornercorner with one NbO6 octahedra and corners with two equivalent TiO6 octahedra. The corner-sharing octahedra tilt angles range from 22–27°. There are a spread of Ti–O bond distances ranging from 1.91–2.09 Å. Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share a cornercorner with one TiO6 octahedra and corners with two equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 27–29°. There are a spread of Nb–O bond distances ranging from 1.89–2.25 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to four Ti4+ atoms to form distorted OTi4 trigonal pyramids that share corners with two equivalent OTi4 trigonal pyramids and edges with two equivalent OTi3Nb trigonal pyramids. In the second O2- site, O2- is bonded to three Ti4+ and one Nb5+ atom to form distorted OTi3Nb trigonal pyramids that share corners with two equivalent OTi3Nb trigonal pyramids and edges with two equivalent OTi4 trigonal pyramids. In the third O2- site, O2- is bonded in a distorted linear geometry to two equivalent Rb1+, one Ti4+, and one Nb5+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Rb1+ and two Ti4+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Rb1+, one Ti4+, and one Nb5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Rb1+, one Ti4+, and one Nb5+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Rb1+ and two Ti4+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Ti4+ and two equivalent Nb5+ atoms. In the ninth O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti4+ atoms.