Materials Data on RbTaO3 by Materials Project
RbTaO3 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 4-coordinate geometry to eight O2- atoms. There are a spread of Rb–O bond distances ranging from 2.69–3.15 Å. In the second Rb1+ site, Rb1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.81 Å) and two longer (2.88 Å) Rb–O bond lengths. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Ta–O bond distances ranging from 1.94–2.08 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Ta–O bond distances ranging from 1.83–2.35 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to one Rb1+ and three Ta5+ atoms to form distorted edge-sharing ORbTa3 trigonal pyramids. In the second O2- site, O2- is bonded in a linear geometry to two equivalent Rb1+ and two Ta5+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to three Rb1+ and one Ta5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Rb1+ and two Ta5+ atoms.